David Burton Elementary Number Theory Solutions Chapter 2 Divisibility Theory In The Integers Exercise 2.1

David Burton Elementary Number Theory Solutions Chapter 2 Divisibility Theory In The Integers

Page 15 Problem 1 Answer

Here, we have to prove that a number is triangular if and only if it is of the form n(n+1)/2 for some n ≥ 1. It’s given that each of the numbers 1 = 1, 3 = 1 + 2, 6 = 1 + 2 + 3, 10 = 1 + 2 + 3 + 4,… represents the number of dots that can be arranged evenly in an equilateral triangle:

David Burton Elementary Number Theory Solutions Chapter 2 Divisibility Theory In The Integers Exercise 2.1 Page 15 Problem 1 Answer Image 1

Proof: Remember that we proved in sec 1.1 that, 1 + 2 + 3 + …. + n = \(\frac{n(n+1)}{2}\). So, if f is triangular, then for some n, 1 + 2 + 3 + …. + n = f by definition, and so f = \(\frac{n(n+1)}{2}\) for some n, then

f = 1 + 2 + 3 + … + n

Thus, we proved that a number is triangular if and only if it is of the form n(n+1)/2 for some n ≥ 1

Here, we have to prove that the integer n is a triangular number if and only if 8n + 1 is a perfect square. it’s given that each of the numbers 1 = 1, 3 = 1 + 2, 6 = 1 + 2 + 3, 10 = 1 + 2 + 3 + 4,… represents the number of dots that can be arranged evenly in an equilateral triangle:

David Burton Elementary Number Theory Solutions Chapter 2 Divisibility Theory In The Integers Exercise 2.1 Page 15 Problem 1 Answer Image 2

Proof: (⇒) if n is triangular, then there is a k ∃ n = \(\frac{k(k+1)}{2}\).

∴ 8n = 4k(k+1)

8n + 1 = 4k(k+1) + 1

= 4k2 + 4k + 1

= (2k+1)2

Therefore n is triangular ⇒ 8n + 1 is a perfect square.

David Burton Elementary Number Theory Solutions Chapter 2 Divisibility Theory In The Integers Exercise 2.1

if 8n + 1 is a perfect square, then there is an integer k ∃ k2 = 8n + 1. Note that 8n+1 must be odd. k2 is odd, and so k is odd, so there is an r ∃ 2r + 1 = k

(2r+1)2 = 8n + 1

4r2 + 4r + 1 = 8n + 1

4r(r+1) = 8n

\(\frac{r(r+1)}{2}\) = n

Therefore, 8n + 1 is a perfect square ⇒ n is triangular.

Thus, we proved that integer n is a triangular number if and only if 8n+1 is a perfect square.

Here, we have to prove that the sum of any two consecutive triangular numbers is a perfect square. It’s given that each of the numbers, 1 = 1,3 = 1 + 2,6 = 1 + 2 + 3,10 = 1 + 2 + 3 + 4,… represents the number of dots that can be arranged evenly in an equilateral triangle:

David Burton Elementary Number Theory Solutions Chapter 2 Divisibility Theory In The Integers Exercise 2.1 Page 15 Problem 1 Answer Image 3

Proof: We want to prove that if k and l are consecutive triangular numbers, then k+l is a perfect square.

Let, 1 + 2 + 3 + ⋯ + n = k, then 1 + 2 + 3 + ⋯ + n + n + 1 = l

∴ k + l = \(\frac{n(n+1)}{2}+\frac{n(n+1)}{2}+(n+1)\)

= n(n+1) = (n+1)

= (n+1)(n+1)

So, k + 1 is a perfect square.

Thus, we proved that the sum of any two consecutive triangular numbers is a perfect square.

Here, we have to prove that if n is a triangular number, then so are 9n + 1,25n + 3, and 49n + 6.

It’s given that each of the numbers, 1 = 1,3 = 1 + 2,6 = 1 + 2 + 3,10 = 1 + 2 + 3 + 4,… represents the number of dots that can be arranged evenly in an equilateral triangle:

David Burton Elementary Number Theory Solutions Chapter 2 Divisibility Theory In The Integers Exercise 2.1 Page 15 Problem 1 Answer Image 4

Proof : Let 1 + 2 + 3 + ⋯ + k = n, then

9n + 1 = \(\frac{9 k(k+1)}{2}+1=\frac{\left.9 k^2+9 k+2\right)}{2}=\frac{(3 k+1)(3 k+2)}{2}=\frac{s(s+1)}{2}^{\text {for } s=3 k+1}\) 9n + 1 is a triangular.

25n + 3 = \(\frac{25 k(k+1)}{2}+3=\frac{\left.25 k^2+25 k+6\right)}{2}=\frac{(5 k+2)(5 k+3)}{2}=\frac{s(s+1)}{2}\) for s = 5k+2, thus 25n + 3 is triangular

49n + 6 = \(\frac{49 k(k+1)}{2}+6=\frac{\left.49 k^2+49 k+12\right)}{2}=\frac{(7 k+3)(7 k+4)}{2}=\frac{s(s+1)}{2}\) for s = 7k + 2, thus 49n + 6 is triangular.

Thus, proved that if n is a triangular number, then so are 9n + 1, 25n + 3, and 49n + 6.

David Burton Elementary Number Theory Chapter 2 Exercise 2.1 solutions

David Burton Elementary Number Theory Solutions Chapter 2 Divisibility Theory In The Integers Exercise 2.1 Page 15 Problem 3 Answer

Here, we have to derive the following formula for the sum of triangular numbers, attributed to the Hindu mathematician Aryabhata,

t1+ t2 + t3 + …. + \(\frac{n(n+1)(n+2)}{6}\) n ≥ 1. It’s given that, tk-1 + tk = k2

Proof: Recall from ex 1 (c) in sec 1.1,

1.2 + 2.3 + …. + n.(n+1) = \(\frac{n(n+1)(n+2)}{3}\), n ≥ 1

∴ \(\frac{1 \cdot 2}{2}+\frac{2 \cdot 3}{2}+\cdots+\frac{n \cdot(n+1)}{2}=\frac{n(n+1)(n+2)}{6}\)

Note that each term k can be written as \(\frac{k(k+1)}{2}=t_k\)

∴ t1 + t2 + t3 + …. + \(\frac{n(n+1)(n+2)}{6}\)

Thus, we derive the following formula for the sum of triangular numbers

t1 + t2 + t3 + …. + \(\frac{n(n+1)(n+2)}{6}\) n ≥ 1.

 

Page 16 Problem 4 Answer

Here, we have to prove that the square of any odd multiple of 3 is the difference of two triangular numbers specifically, that 9(2n+1)2 = t9n+4 − t3n+1

Proof : We want to prove that the square of any odd multiple of 3 is the difference of two triangular numbers.

Since,

\(t_k=\frac{k(k+1)}{2}\), then

\(t_{9 n+4}=\frac{(9 n+4)(9 n+5)}{2}, t_{3 n+1}=\frac{(3 n+1)(3 n+2)}{2}\)

Therefore,

\(t_{9 n+4}-t_{3 n+1}=\frac{\left(81 n^2+81 n+20\right)-\left(9 n^2+9 n+2\right)}{2}\)

= \(\frac{72 n^2+72 n+18}{2}\) = 36n2 + 36n + 9

= 9(4n2 + 4n + 1) = 9(2n+1)2

Thus, we proved that the square of any odd multiple of 3 is the difference of two triangular numbers specifically, that 9(2n+1){2} = t9n+4 − t3n+1

 

David Burton Elementary Number Theory Solutions Chapter 2 Divisibility Theory In The Integers Exercise 2.1 Page 16 Problem 5 Answer

Here, we have to find two triangular numbers whose sum and difference are also triangular numbers.

From the list of the first ten triangular numbers, 1,3,6,10,15,21,28,36,45,55, if we look carefully, it is not hard to see that the number we searching for are A = 15 and B = 21.Really, A + B = 36 triangular number, B − A = 6 triangular number.

So, make a list of first ten triangular numbers i.e 0,1,3,6,10,15,21,28,36,45,55

Here, we have to find three successive triangular numbers whose product is a perfect square.

Product of three successive triangular numbers is given by,

\(\frac{n(n+1)}{2} \cdot \frac{(n+1)(n+2)}{2} \cdot \frac{(n+2)(n+3)}{2}\) = \(\frac{n(n+1)^2(n+2)^2(n+3)}{8}\)

for some positive integer n. We can conclude that 2 divide n+1 or n+2,then 4 must divide (n+1)2 or (n+2)2.So that, if we find n such that n(n+3) divided by 2 gives the perfect square, our problem was solved. It is not hard to conclude that we need to chose n = 3

Really, for n = 3

\(\frac{3 \cdot 4 \cdot 4 \cdot 5 \cdot 5 \cdot 6}{8}\) = 32 . 52 . 4 = 302 = 900

Thus, use that the product of the three successive triangular numbers is given by

\(\frac{n(n+1)}{2} \cdot \frac{(n+1)(n+2)}{2} \cdot \frac{(n+2)(n+3)}{2}\) = \(\frac{n(n+1)^2(n+2)^2(n+3)}{8}\) , for some positive integer n

Here, we have to find the three successive triangular numbers whose sum is a perfect square.

From the list of first ten triangular numbers 1,3,6,10,15,21,28,36,45,55, if we look carefully, it is not hard to see that the number we searching for are A = 15,B = 21 and C = 28 Really, A + B + C = 64 perfect square

Thus, make a list of first ten triangular numbers i.e 0,1,3,6,10,15,21,28,36,45,55

Solutions to Chapter 2 Exercise 2.1 Burton Number Theory

Page 16 Problem 6 Answer

Here, we have to prove that t4n(n+1) is also a square if the triangular number tn is a perfect square.

Proof: Assume

tn = k2 = \(\frac{n(n+1)}{2}\), then 2k2 = n(n+1)

t4n(n+1)= \(\frac{4 n(n+1)(4 n(n+1)+1)}{2}\)

= \(4 \cdot 2 k^2\left[4 n^2+4 n+1\right]\)

= 4k2(2n+1)2

= [2k(2n+1)]2

Thus, we prove that t4n(n+1) is also a square.

Here, we have to use part (a) to find three examples of squares that are also triangular numbers.

Using part (a) t1 = 1 is a perfect square. t4⋅1(1+1) = t8 = 36 is a perfect square.

\(t_{4 \cdot 8(8+1)}=t_{288}=\frac{288(288+1)}{2}\) = 41616 = 2042 is a perfect square.

Thus, we used part (a) to find three examples of squares that are also triangular numbers.

 

Page 16 Problem 7 Answer

Here, we have to show that the difference between the squares of two consecutive triangular numbers is always a cube.

Proof : We want to prove the difference between the squares of two consecutive triangular numbers is always a cube.

Since, \(t_{n+1}=\frac{(n+1)(n+2)}{2}, t_n=\frac{n(n+1)}{2}\)

∴ \(t_{n+1}^2-t_n^2=\frac{(n+1)^2(n+2)^2-(n+1)^2 n^2}{4}\)

= \(\frac{(n+1)^2\left[n^2+4 n+4=n^2\right]}{4}\) for n ≥ 1

= \(\frac{(n+1)^2(4 n+4)}{4}=(n+1)^3\)

Thus, show that the difference between the squares of two consecutive triangular numbers is always a cube.

 

David Burton Elementary Number Theory Solutions Chapter 2 Divisibility Theory In The Integers Exercise 2.1 Page 16 Problem 8 Answer

Here, we have to prove that the sum of the reciprocals of the first n triangular numbers is less than 2 that is,\(\frac{1}{1}+\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+\cdots+\frac{1}{t_n}<2\). It’s given that \(\frac{2}{n(n+1)}=2\left(\frac{1}{n}-\frac{1}{n+1}\right)\)

Proof:

Note that,

\(\frac{1}{t_k}=\frac{1}{\frac{k(k+1)}{2}}=\frac{2}{k(k+1)}=2\left(\frac{1}{k}-\frac{1}{k+1}\right)\)

∴ \(\frac{1}{1}+\frac{1}{3}+\cdots+\frac{1}{t_n}\)

= \(2\left(\frac{1}{1}-\frac{1}{2}\right)+2\left(\frac{1}{2}-\frac{1}{3}\right)+\cdots+2\left(\frac{1}{n}-\frac{1}{n+1}\right)\)

=\(2\left(\frac{1}{1}-\frac{1}{n+1}\right)=2\left(1-\frac{1}{n+1}\right)\)

Since,

\(n>0 \Rightarrow n+1>0 \Longrightarrow \frac{1}{n+1}>0 \Longrightarrow-\frac{1}{n+1}<0\) \(\Longrightarrow 1-\frac{1}{n+1}<1 \Longrightarrow 2\left(1-\frac{1}{n+1}\right)<2\)

that is \(\frac{1}{1}+\frac{1}{3}+\cdots+\frac{1}{t_n}<2\)

Thus, we proved that sum of the reciprocals of the first n triangular numbers is less than 2 that is 1

\(\frac{1}{1}+\frac{1}{3}+\frac{1}{6}+\frac{1}{10}+\cdots+\frac{1}{t_n}<2\)

Divisibility Theory Exercise 2.1 answers David Burton

David Burton Elementary Number Theory Solutions Chapter 2 Divisibility Theory In The Integers Exercise 2.1 Page 16 Problem 9 Answer

Here, we have to establish the identity t{x} = t{y} + t{z}, where \(x=\frac{n(n+3)}{2}+1 \quad y=n+1 \quad z=\frac{n(n+3)}{2}\) and n ≥ 1, thereby proving that there are infinitely many triangular numbers that are the sum of two other such numbers.

Proof:

R.H.S

= \(t_y+t_z=\frac{(n+1)(n+2)}{2}+\frac{\frac{n(n+3)}{2}\left[\frac{n(n+3)}{2}+1\right]}{2}\)

= \(\frac{2\left[\frac{(n+1)(n+2)}{2}\right]+\frac{n(n+3)}{2}\left[\frac{n(n+3)}{2}+1\right]}{2}\)

= \(\frac{2\left[\frac{n^2+3 n+2}{2}\right]+\frac{n(n+3)}{2}\left[\frac{n(n+3)}{2}+1\right]}{2}\)

= \(\frac{2\left[\frac{n(n+3)}{2}+1\right]+\frac{n(n+3)}{2}\left[\frac{n(n+3)}{2}+1\right]}{2}\)

= \(\frac{\left[\frac{n(n+3)}{2}+1\right]\left[\frac{n(n+3)}{2}+1+1\right]}{2}\)

= tx = L.H.S

Thus, we prove that t{x} = t{y} + t{z} where \(x=\frac{n(n+3)}{2}+1 \quad y=n+1 \quad z=\frac{n(n+3)}{2}\)

Here, we have to find three examples of triangular numbers that are sums of two other triangular numbers.

Using part (a):

​n = 1 : t3 = t2 + t2, or 6 = 3 + 3

n = 2 : t6 = t3 + t5, or 21 = 6 + 15

n = 3 : t10 = t4 + t9, or 55 = 10 + 45

Thus, we find three examples of triangular numbers that are sums of two other triangular numbers, they are

​n = 1 : t3 = t2 + t2, or 6 = 3 + 3

n = 2 : t6 = t3 + t5, or 21 = 6 + 15

n = 3 : t10 = t4 + t9, or 55 = 10 + 45

 

David Burton Elementary Number Theory Solutions Chapter 2 Divisibility Theory In The Integers Exercise 2.1 Page 16 Problem 10 Answer

Here, we have to prove that pn = \(\frac{n(3 n-1)}{2}\), n ≥ 1. It’s given that each of the numbers 1, 5 = 1 + 4, 12 = 1 + 4 + 7, 22 = 1 + 4 + 7 + 10,… represents the number of dots that can be arranged evenly in a pentagon:

David Burton Elementary Number Theory Solutions Chapter 2 Divisibility Theory In The Integers Exercise 2.1 Page 16 Problem 10 Answer

Let pn denotes nth pentagonal number where, p1 = 1

pn = pn-1 + 3n – 2, n ≥ 2

We need to prove that n th pentagonal number is given by formula pn = \(\frac{n(3 n-1)}{2}\) equation (1) for each positive integer n for which Eq (1) holds.

For n = 1 eq (1) is true, so that 1 belongs to the set S.

We assume that Eq (1) is true for a fixed integer k, so that for this k, pk = \(\frac{k(3 k-1)}{2}\) and we attempt to prove that validity of the formula for k + 1. Using the definition of the pentagonal numbers we obtain that, pk+1 = pk + 3(k+1)-2

Next, from hypothesis that Eq (1) is correct for k we have that

pk+1 = pk + 3(k+1)-2

= \(\frac{k(3 k-1)}{2}+\frac{6(k+1)-4}{2}\)

= \(\frac{3 k^2-k+6 k+6-4}{2}\)

= \(\frac{3 k^2+5 k+2}{2}\)

= \(\frac{3 k^2+3 k+2 k+2}{2}\)

= \(\frac{3 k(k+1)+2(k+1)}{2}\)

= \(\frac{(k+1)(3(k+1)-1)}{2}\)

But this says that Eq (1) holds when n = k + 1,putting the integer k+1 in S so, that k+1 is in S whenever k is in S.According to the induction principle, S must be the set of all positive integers.

Thus, we use the definition of the pentagonal numbers and the induction principle to prove pn = \(\frac{n(3 n-1)}{2}\), n ≥ 1

Burton Number Theory Divisibility Exercise 2.1 solutions

David Burton Elementary Number Theory Solutions Chapter 2 Divisibility Theory In The Integers Exercise 2.1 Page 16 Problem 11 Answer

Here, we have to verify the relations between the pentagonal, square, and triangular numbers: pn = tn-1 + n2

Let n be fixed arbitrary integer such that n ≥ 2, then

\(t_{n-1}+n^2 \stackrel{(1)}{=} \frac{n(n+1)}{2}+n^2\)

= \(\frac{n^2+n+2 n^2}{2}\)

= \(\frac{n(3 n+1)}{2}\)

= pn

So, that this relation is correct.

Thus, we verified the relations between the pentagonal, square, and triangular numbers ; pn = tn-1 + n2

Here, we have to verify the relations between the pentagonal, square, and triangular numbers: pn = 3tn-1 + n = 2tn-1 + tn

Let n be fixed arbitrary integer such that n ≥ 2,then,

\(3 t_{n-1}+n \stackrel{(1)}{=} \frac{n(n-1)}{2}+n\)

= \(\frac{3 n^2-3 n+2 n}{2}\)

= \(\frac{3 n^2-n}{2}\)

= \(\frac{n(3 n+1)}{2}\)

= \(p_n\)

= \(\frac{n(3 n+1)}{2}\)

= \(\frac{3 n^2-n}{2}\)

= \(\frac{2 n^2-2 n+n^2+n}{2}\)

= \(2 \frac{n(n-1)}{2}+\frac{n(n+1)}{2}\)

= 2tn-1 + tn

So, the these relations are correct

Thus, we verified the relations between the pentagonal, square, and triangular numbers: pn = 3tn-1 + n = 2tn-1 + tn

David Burton Elementary Number Theory Solutions Chapter 1 Preliminaries Exercise 1.1

David Burton Elementary Number Theory Solutions Chapter 1 Preliminaries

Page 7 Problem 2 Answer

Given: a + ar + ar2 + …. + arn = \(\frac{a\left(r^{n+1}-1\right)}{r-1}\)

If r ≠ 1, we have to show that for any positive integer n

We want to prove that:

a + ar + ar2 + …. + arn = \(\frac{a\left(r^{n+1}-1\right)}{r-1}\)(1)

Let S be the set of all positive integers for which Equation (1) is true.

When r = 2, a + ar + ar2 = a(r2 + r + 1)

R.H.S:

\(\frac{a\left(r^3-1\right)}{r-1}=\frac{a(r-1)\left(r^2+r+1\right)}{(r-1)}\) = a(r2 + r + 1)

From (1) and (2), r = 2 satisfies

Equation (1) ⇒ 2 ∈ S Let K ∈ S then

a + ar + …. + ark = \(\frac{a\left(r^{k+1}-1\right)}{r-1}\) + ark+1

Now for

r = k + 1, a + ar + … + ark + ark+1 = \(\frac{a\left(r^{k+1}-1\right)}{r-1}\)

= \(\frac{a}{r-1}\left[r^{k+1}-1+(r-1) r^{k+1}\right]=\frac{a}{r-1}\left[r^{k+2}-1\right]\)

Which is the R.H.S of Eq.(1) when r=k+1

Thus k+1 ∈ S then S is the set of all positive integers r ≥ 2,thus Eq.(1) is true for all r ≥ 2

We get, a + ar + ar2 + …. + arn = \(\frac{a\left(r^{n+1}-1\right)}{r-1}\)

David Burton Elementary Number Theory Chapter 1 Exercise 1.1 Solutions

David Burton Elementary Number Theory Solutions Chapter 1 Preliminaries Exercise 1.1 Page 7 Problem 3 Answer

Given: an−1 = (a−1)(an-1 + an-2 + an-3 + ⋯ + a + 1)

By using the Second Principle of Finite Induction we have to establish that for all n ≥ 1

an-1 = (a-1)(an-1 + an-2 + … + a + 1)

Proof: We prove it by induction. For n = 1, the relation trivially holds. Let this hold for all numbers less or equal to k i.e.

ak−1 = (a−1)(ak-1 + ak-2 + ⋯ + a + 1)

Then

ak+1 − 1 = ak+1 − ak + ak − 1

= ak(a−1) + (a−1)(ak-1 + ak-2 + ⋯ + a + 1)

= (a−1)(ak + ak-1 + ak-2 + ⋯ + a + 1)

This shows that the relation holds for number k implies it holds for k+1. Hence by principle of finite induction, this holds for all n ≥ 1.

So, the relation holds for number k implies it holds for k + 1.

Hence by principle of finite induction, this holds for all n ≥ 1.

David Burton Elementary Number Theory Solutions Chapter 1 Preliminaries Exercise 1.1

Page 7 Problem 4 Answer

Given:

n3 = (13 + 23 + ⋯ + n3) − (13 + 23 + ⋯ + (n−1)3).

We have to prove that the cube of any integer can be written as the difference of two squares

we use the relation that

13 + 23 + … + n3 = \(\left(\frac{n(n+1)}{2}\right)^2\)

We know that

n3 = (13 + 23 + ⋯ + n3) − (13 + 23 + ⋯ + (n−1)3)

Using the above relation, we get

n3 = \(\left(\frac{n(n+1)}{2}\right)^2-\left(\frac{(n-1) n}{2}\right)^2\)

Where the terms \(\left(\frac{n(n+1)}{2}\right) \text { and }\left(\frac{(n-1) n}{2}\right)\) are integers.

We get n3 = \(\left(\frac{n(n+1)}{2}\right)^2-\left(\frac{(n-1) n}{2}\right)^2\)

Where the terms \(\left(\frac{n(n+1)}{2}\right) \text { and }\left(\frac{(n-1) n}{2}\right)\) are integers.

Solutions To Chapter 1 Exercise 1.1 Burton Elementary Number Theory

David Burton Elementary Number Theory Solutions Chapter 1 Preliminaries Exercise 1.1 Page 7 Problem 5 Answer

We need to find the values of n ≤ 7 for which n!+1 is a perfect square.

We need to find the values of n ≤ 7 for which n!+1 is a perfect square.

n:1 ⇒ ​n! + l = 2

n:2 ⇒​ n! + 1 = 3

n:3 ⇒ ​n! + l = 7

n:4 ⇒ ​n! + 1 = 52

n:5 ⇒​ n! + 1 = 112

​n = 6 ⇒ ​n!+1 = 721

n = 7 ⇒​ n!+1 = 5041 = 712

Thus for n = 4,5,7 n!+1 is a perfect square

For n = 4,5,7,n! + 1 is a perfect square.

Given -​ For positive integers m and n,(mn)! = m!n! and (m+n)! = m!+n!.

We will determine whether the given statement is true or false.

We will use the known facts.

False.

Because(3.2)! = 720

3!.2! = 6.2

= 12

So (3.2)! ≠ 3!.2!

(3+2)! = 5!

= 120

3! + 2! = 6 + 2

= 8

So (3+2)! ≠ 3! + 2!

The given statement is false.

 

Page 7 Problem 6 Answer

We have to prove that n! > n2 for every integer n ≥ 4, where as n! > n3 for every integer n ≥ 6.

We prove it via finite induction. We know 4! = 24 ≥ 16 = 42 thus it works for case n = 4. Let this true for some integer k > 4. i.e. k! > k{2}.

Then

(k+1)! = (k+1)k! > (k+1)k2 > (k+1)2

[Note* here we use k2 ≥ k+1]

This shows n! > n2 for all n ≥ 4 by induction.

For n = 6, we have 6! = 720 > 216 = 63. Let this be true for some integer k i.e. k! > k3, then

(k+1)! = (k+1)k! > (k+1)k3 > (k+1)(k+1)2 = (k+1)3

[There we use k3 >(k+1)2 for all k ≥ 3].

This shows n! > n3 for all n ≥ 6.

We get that n! > n3 for all n ≥ 6.

 

Page 7 Problem 8 Answer

Given: 2.6.10.14…(4n-2) = \(\frac{(2 n) !}{n !}\)

We have to verify that for all n ≥ 1

We have to prove that:

2.6.10.14…(4n-2) = \(\frac{(2 n) !}{n !}\)

Let S be the set of all positive integers for which Equation (1) is true.

For n = 1, 2 = \(\frac{(2) !}{1 !}\) = 2 thus 1 ∈ S

Assume K ∈ S then

2.6.10.14….(4k-2) = \(\frac{(2 k) !}{k !}\)

Now for

r = k + 1, 2.6.10.14…(4k-2).(4k+2) = \(\frac{(2 k) !}{k !}\)2(2k+1) = \(\frac{(2 k+1) !(2)}{k !} \cdot \frac{(k+1)}{(k+1)}\) = \(\frac{(2 k+2) !}{(k+1) !}=\frac{[2(k+1)] !}{(k+1) !}\) which is R.H.S of Eq(1)

When n = k + 1, thus k + 1 ∈ S

So, 2.6.10.14…(4n-2) = \(\frac{(2 n) !}{n !}\) is true for all n ≥ 1.

thus, 2.6.10.14…(4n-2) = \(\frac{(2 n) !}{n !}\) is true for all n ≥ 1.

By using (a)part we have to obtain that the inequality 2n(n!)2 ≤ (2n)! for all n ≥ 1.

Proof: 2n(n!) ≤ \(\frac{(2 n) !}{n !}\)

Using part (a): 2⋅6⋅10⋅14⋯(4n−2) ≥ 2n(n!)

Let S be the set of all positve integers for which Eq.(1) is true.

For n = 1,2 ≥ 2 thus 1 ∈ S

Assume k ∈ S then 2⋅6⋅10⋅14⋯(4k−2) ≥ 2k(k!)

Now for r = k+1,2⋅6⋅10⋅14⋯(4k−2)⋅(4k+2) ≥ 2k(k!)(4k+2)

= 2k(k!)2(2k+1)=2k+1(k+1)!

Therefore, k + 1 satisfies Eq.(1), thus k+1 ∈ S

Thus, 2⋅6⋅10⋅14⋯(4n−2) ≥ 2n(n!)

We get, 2.6.10.14…(4n-2) ≥ 2n(n!) is true for all n ≥ 1.

 

David Burton Elementary Number Theory Solutions Chapter 1 Preliminaries Exercise 1.1 Page 7 Problem 9 Answer

We have to Establish the Bernoulli inequality: If 1 + a > 0, then(1+a)n ≥ 1 + na for all n ≥ 1.

If 1 + a > 0, we need to prove that for each integer n ≥ 1 inequality

(1+a)n ≥ 1 + na…………(1) is correct.

Let S be the set of positive integers n for which Eq.1 holds. For n = 1 (1) is true, so that 1 belongs to the set S. We assume that inequality (1) is true for a fixed integer k, so that for this k

(1+a)k ≥ 1 + ka

and we attempt to prove the validity of the formula for k+1. Next, from hypothesis that inequality(1) is correct for k we have that

​(1+a)k+1 = (1+a)k(1+a)
​​
hypothesis

≥ (1+ka)(1+a)

= 1 + ka + a + ka2

= 1 + (k+1)a

But this says that inequality (1) holds when n = k + 1, putting the integer k+1 in S so that k+1 is in S whenever k is in S. According to the induction principle, S must be the set of all positive integers.

So, the Bernoullis’s ldentity is established.

So, the Bernoullis’s ldentity is established.

Elementary Number Theory Burton Exercise 1.1 Answers

Page 7 Problem 10 Answer

Given: \(\frac{1}{1^2}+\frac{1}{2^2}+\frac{1}{3^2}+\cdots+\frac{1}{n^2} \leq 2-\frac{1}{n}\)

To find: For all n ≥ 1,prove the following by mathematical induction

\(\frac{1}{1^2}+\frac{1}{2^2}+\frac{1}{3^2}+\cdots+\frac{1}{n^2} \leq 2-\frac{1}{n}\)

For n = 1, we have

\(\frac{1}{1^2} \leq 2-\frac{1}{1}=n\)

so it holds.

Let the proposition hold for any number k, i.e. \(\frac{1}{1^2}+\frac{1}{2^2}+\cdots+\frac{1}{k^2} \leq 2-\frac{1}{k}\)

Then

\(\frac{1}{1^2}+\frac{1}{2^2}+\cdots+\frac{1}{k^2}+\frac{1}{(k+1)^2} \leq 2-\frac{1}{k}+\frac{1}{(k+1)^2}\) = \(2-\frac{1}{k+1}\left(\frac{k+1}{k}-\frac{1}{k+1}\right)\)

= \(2-\frac{1}{k+1}\left(\frac{(k+1)^2-k}{k(k+1)}\right)\)

= \(2-\frac{1}{k+1}\left(\frac{k(k+1)+1}{k(k+1)}\right)\)

< \(2-\frac{1}{k+1}\)

This shows that the relation holds for any n ≥ 1.

This shows that the relation holds for any n ≥ 1.

Given: \(\frac{1}{2}+\frac{2}{2^2}+\frac{3}{2^3}+\cdots+\frac{n}{2^n}=2-\frac{n+2}{2^n}\)

To find: For all n ≥ 1, prove the following by mathematical induction:

\(\frac{1}{2}+\frac{2}{2^2}+\frac{3}{2^3}+\cdots+\frac{n}{2^n}=2-\frac{n+2}{2^n}\)

For n = 1, we have

\(2-\frac{1+2}{2^1}=2-\frac{3}{2}=\frac{1}{2}\)

So the relation holds for n = 1.

Let the relation hold for some integer k, i.e.

\(\frac{1}{2}+\frac{2}{2^2}+\frac{3}{2^2}+\cdots+\frac{k}{2^k}=2-\frac{k+2}{2^k}\)

then

\(\frac{1}{2}+\frac{2}{2^2}+\frac{3}{2^2}+\cdots+\frac{k}{2^k}+\frac{k+1}{2^{k+1}}\) = \(2-\frac{k+2}{2^k}+\frac{k+1}{2^{k+1}}\)

= \(2-\left(\frac{2(k+2)-(k+1)}{2^{k+1}}\right)\)

= \(2-\frac{k+3}{2^{k+1}}\)

This shows the relation holds for all n ≥ 1.

This shows the relation holds for all n ≥ 1.

 

David Burton Elementary Number Theory Solutions Chapter 1 Preliminaries Exercise 1.1 Page 7 Problem 11 Answer

We have to show that the expression (2n)!/2nn! is an integer for all. n ≥ 0

From problem no 8, we have

2.6.10.14….(4n-2) = \(\frac{(2 n) !}{n !}\)

factoring 2 from each term on left side, we get

2n . 1.3.5.7…(2n-1) = \(\frac{(2 n) !}{n !}\)

This gives \(\frac{(2 n) !}{n ! 2^n}\) = 1.3.5.7…(2n-1) which is an integer.

We get \(\frac{(2 n) !}{n ! 2^n}\) = 1.3.5.7…(2n-1) which is an integer.

 

Page 7 Problem 12 Answer

Given: Consider the function defined by

T(n) = \(\begin{cases}\frac{3 n+1}{2} & \text { for } n \text { odd } \\ \frac{n}{2} & \text { for } n \text { ever }\end{cases}\)

The 3n+1 conjecture is the claim that starting from any integer n > 1, the sequence of iterates T(n),T(T(n)),T(T(T(n))),…, eventually reaches the integer 1 and subsequently runs through the values 1 and 2 . This has been verified for all n ≤ 1016.

Confirm the conjecture in the cases n = 21 and n = 23.

If n = 1, then we get T(1) = \(\frac{1}{2}(3 \cdot 1+1)=2\) and if n = 2, we get T(2) = 2/2 = 1.

For n = 21, we get the following result.

\(\begin{array}{l|l}
\mathrm{k} & T^k(21) \\
0 & 21 \\
1 & 32 \\
2 & 16 \\
3 & 8 \\
4 & 4 \\
5 & 2
\end{array}\) For n = 23, we get following result.

\(\begin{array}{l|l}
\mathrm{k} & T^k( \\
0 & 23 \\
1 & 35 \\
2 & 53 \\
3 & 80 \\
4 & 40 \\
5 & 20 \\
6 & 10 \\
7 & 5 \\
8 & 8 \\
9 & 4 \\
10 & 2
\end{array}\)

We get,

For n = 21

\(\begin{array}{l|l}
\mathrm{k} & T^k(21) \\
0 & 21 \\
1 & 32 \\
2 & 16 \\
3 & 8 \\
4 & 4 \\
5 & 2
\end{array}\)

for n = 23

\(\begin{array}{l|l}
\mathrm{k} & T^k( \\
0 & 23 \\
1 & 35 \\
2 & 53 \\
3 & 80 \\
4 & 40 \\
5 & 20 \\
6 & 10 \\
7 & 5 \\
8 & 8 \\
9 & 4 \\
10 & 2
\end{array}\)

 

Page 8 Problem 13 Answer

Given: Suppose that the numbers an are defined inductively by

a1= 1, a2 = 2, a3 = 3a1=1, a2 = 2, a3 = 3, and

an = an-1 + an-2 + an-3 for all n ≥ 4.

To find: Use the Second Principle of Finite Induction to show that an < 2n for every positive integer n.

Given that a1 = 1, a2 = 2, a3 = 3 and

an = an-1 + an-2 + an-3

for all n ≥ 4. Then a{n} < 2{n}.

For base case, a{n} = 1 + 2 + 3 = 6<2{4} = 16.

Let us assume that for all numbers r < k, the inequality be true.

i.e.

aτ < 2r

for all r ≤ k. Then ak+1

​= ak + ak-1 + ak-2

< 2k + 2k-1 + 2k-2

= 2k-2(1+2+4)

< 2k+1

Or,

ak+1 < 2k+1

This shows that by strong induction, a{n} < 2{n} for all n ≥ 4.

This shows that by strong induction, a{n} < 2{n} for all n ≥ 4.

Chapter 1 Exercise 1.1 Burton Number Theory Key

David Burton Elementary Number Theory Solutions Chapter 1 Preliminaries Exercise 1.1 Page 8 Problem 14 Answer

Given: If the numbers an are defined by a1 = 11, a2 = 21, and an = 3an-1 – 2an-2 for n ≥ 3

To prove: an = 5.2n + 1 n ≥ 1

Let a1 = 11 and a2 = 21 and an be defined by

an = 3an-1 − 2an-2

Then an = 5⋅2n+1,n ≥ 1. This is true for n = 1,2,3 since

​a1 = 5⋅2 + 1 = 11

a2 = 5⋅4 + 1 = 21

a3 = 41 = 3⋅21 − 2⋅11

Let this be true for all integers r ≤ k. i.e.

ar = 5⋅2r + 1,r ≤ k

Then

ak+1 = 3ak − 2ak-1

= 3(5⋅2k+1) − 2(5⋅2k-1+1)

= 5⋅2k-1(6−2) + 3 − 2

= 5⋅2k+1+1

which shows the result hold for k+1 as well.

Therefore by strong induction, the result holds for all n ≥ 1.

Therefore by strong induction, the result holds for all n ≥ 1.

 

Page 10 Problem 1 Answer

We have to Derive Newton’s identity

\(\left(\begin{array}{c}
n \\
k
\end{array}\right)\left(\begin{array}{c}
k \\
r
\end{array}\right)=\left(\begin{array}{c}
n \\
r
\end{array}\right)\left(\begin{array}{c}
n-r \\
k-r
\end{array}\right) \quad n \geq k \geq r \geq 0\)

\(\left(\begin{array}{l}
n \\
k
\end{array}\right)\left(\begin{array}{l}
k \\
r
\end{array}\right)\) = \(\frac{n !}{(n-k) ! k !} \cdot \frac{k !}{(k-r) ! r !}\)

= \(\frac{n !}{(n-r) ! r !} \cdot \frac{(n-r) !}{(n-k) !(k-r) !}\)

= \(\left(\begin{array}{l}
n \\
r
\end{array}\right)\left(\begin{array}{l}
n-r \\
k-r
\end{array}\right)\)

We get, \(\left(\begin{array}{l}
n \\
k
\end{array}\right)\left(\begin{array}{l}
k \\
r
\end{array}\right)\) = \(\left(\begin{array}{l}
n \\
r
\end{array}\right)\left(\begin{array}{l}
n-r \\
k-r
\end{array}\right)\)

By the Use of part (a) we have to express \(\left(\begin{array}{l}
n \\
k
\end{array}\right)\) in terms of it predecessor: \(\left(\begin{array}{l}
n \\
k
\end{array}\right)\) = \(\frac{n-k+1}{k}\left(\begin{array}{c}
n \\
k-1
\end{array}\right) \quad n \geq k \geq 1\)

Put r = k – 1, this gives

\(\left(\begin{array}{c}
n \\
k
\end{array}\right)\left(\begin{array}{c}
k \\
k-1
\end{array}\right)=\left(\begin{array}{c}
n \\
k-1
\end{array}\right)\left(\begin{array}{c}
n-k+1 \\
1
\end{array}\right)\)

This gives

\(\left(\begin{array}{l}
n \\
k
\end{array}\right)\)k = \(\left(\begin{array}{c}
n \\
k-1
\end{array}\right)(n-k+1)\) ⇒ \(\frac{(n-k+1)}{k}\left(\begin{array}{c}
n \\
k-1
\end{array}\right)\)

We get, \(\left(\begin{array}{l}
n \\
k
\end{array}\right)\)k = \(\left(\begin{array}{c}
n \\
k-1
\end{array}\right)(n-k+1)\) ⇒ \(\frac{(n-k+1)}{k}\left(\begin{array}{c}
n \\
k-1
\end{array}\right)\)

 

David Burton Elementary Number Theory Solutions Chapter 1 Preliminaries Exercise 1.1 Page 11 Problem 2 Answer

If 2 ≤ k ≤ n-2, show that

\(\left(\begin{array}{l}
n \\
k
\end{array}\right)=\left(\begin{array}{l}
n-2 \\
k-2
\end{array}\right)+2\left(\begin{array}{c}
n-2 \\
k-1
\end{array}\right)+\left(\begin{array}{c}
n-2 \\
k
\end{array}\right)\) n ≥ 4

Proof: let 2 ≤ k ≤ n-2 and n ≥ 4. We want to prove:

\(\left(\begin{array}{l}
n \\
k
\end{array}\right)=\left(\begin{array}{l}
n-2 \\
k-2
\end{array}\right)+2\left(\begin{array}{c}
n-2 \\
k-1
\end{array}\right)+\left(\begin{array}{c}
n-2 \\
k
\end{array}\right)\)

Take the right hand side:

\(\left(\begin{array}{l}
n-2 \\
k-2
\end{array}\right)+2\left(\begin{array}{c}
n-2 \\
k-1
\end{array}\right)+\left(\begin{array}{c}
n-2 \\
k
\end{array}\right)\)

= \(\frac{(n-2) !}{(k-2) !(n-k) !}+\frac{2(n-2) !}{(k-1) !(n-k-1) !}+\frac{(n-2) !}{k !(n-k-2) !}\)

= \(\frac{k(k-1)(n-2) !}{k !(n-k) !}+\frac{2 k(n-k)(n-2) !}{k !(n-k) !}+\frac{(n-k)(n-k-1)(n-2) !}{k !(n-k) !}\)

= \(\frac{\left.(n-2) ! k^2-k+2 k n 2-2 k^2+n^2-n k-n-k_R+k^2+k\right]}{k !(n-k) !}\)

= \(\frac{(n-2) !\left[n^2-n\right]}{k !(n-k) !}=\frac{n(n-1)(n-2) !}{k !(n-k) !}\)

= \(\frac{n !}{k !(n-k) !}=\left(\begin{array}{c}
n \\
k
\end{array}\right)\)

Therefore R.H.S = L.H.S.

We get, \(\left(\begin{array}{l}
n \\
k
\end{array}\right)=\left(\begin{array}{l}
n-2 \\
k-2
\end{array}\right)+2\left(\begin{array}{c}
n-2 \\
k-1
\end{array}\right)+\left(\begin{array}{c}
n-2 \\
k
\end{array}\right)\) n ≥ 4

 

Page 11 Problem 4 Answer

We have to prove the following for n ≥ 1: \(\left(\begin{array}{l}
n \\
r
\end{array}\right)<\left(\begin{array}{c}
n \\
r+1
\end{array}\right)\) if and only if 0 ≤ r < \(\frac{1}{2}(n-1)\).

Proof: for n ≥ 1,

\(\left(\begin{array}{l}
n \\
r
\end{array}\right)<\left(\begin{array}{c}
n \\
r+1
\end{array}\right)\)

<=> \(\frac{n !}{r !(n-r) !}<\frac{n !}{(r+1) !(n-r-1) !}\), 0 ≤ r, 0 ≤ n – r – 1

<=> \(frac{(r+1) !}{r !}<\frac{(n-r) !}{(n-r-1) !}\), 0 ≤ r ≤ n-1

<=> r + 1 < n – r, 0 ≤ r ≤ n-1

<=> 0 ≤ 2r ≤ n-1

<=> 0 ≤ r ≤ \(\frac{1}{2}(n-1)\)

We get, \(\left(\begin{array}{l}
n \\
r
\end{array}\right)<\left(\begin{array}{c}
n \\
r+1
\end{array}\right)\) if and only if 0 ≤ r < \(\frac{1}{2}(n-1)\).

We have to prove the following for n ≥ 1: \(\left(\begin{array}{l}
n \\
r
\end{array}\right)>\left(\begin{array}{c}
n \\
r+1
\end{array}\right)\) if and only if n-1 ≥ r > \(\frac{1}{2}(n-1)\).

For n ≥ 1,

\(\left(\begin{array}{l}
n \\
r
\end{array}\right)>\left(\begin{array}{c}
n \\
r+1
\end{array}\right)\)

<=> \(\frac{n !}{r !(n-r) !}>\frac{n !}{(r+1) !(n-r-1) !}\), r ≥ 0, n – r – 1 ≥ 0

<=> \(frac{(r+1) !}{r !}<\frac{(n-r) !}{(n-r-1) !}\), r ≥ 0, n – r – 1 ≥ 0

<=> 2r > n – 1, n – 1 ≥ r ≥ 0

<=> n – 1 ≥ r ≥ \(\frac{1}{2}(n-1)\) ≥ 0

We get, \(\left(\begin{array}{l}
n \\
r
\end{array}\right)>\left(\begin{array}{c}
n \\
r+1
\end{array}\right)\) if and only if n-1 ≥ r > \(\frac{1}{2}(n-1)\).

We have to prove the following for n ≥ 1:

\(\left(\begin{array}{l}
n \\
r
\end{array}\right)=\left(\begin{array}{c}
n \\
r+1
\end{array}\right)\) if and only if n is odd integer, and r = \(\frac{1}{2}(n-1)\).

for n ≥ 1,

\(\left(\begin{array}{l}
n \\
r
\end{array}\right)=\left(\begin{array}{c}
n \\
r+1
\end{array}\right)\)

<=> r + 1 = n – r, n – 1 ≥ r ≥ 0

<=> 2r = n – 1, n – 1 ≥ r ≥ 0

<=> r = \(\frac{1}{2}(n-1)\), n – 1 ≥ r ≥ 0

We get, \(\left(\begin{array}{l}
n \\
r
\end{array}\right)=\left(\begin{array}{c}
n \\
r+1
\end{array}\right)\) if and only if n is odd integer, and r = \(\frac{1}{2}(n-1)\).

How To Solve Chapter 1 Exercise 1.1 Burton Number Theory

Page 12 Problem 5 Answer

For n ≥ 2, we have to prove that

\(\left(\begin{array}{l}
2 \\
2
\end{array}\right)+\left(\begin{array}{l}
3 \\
2
\end{array}\right)+\left(\begin{array}{l}
4 \\
2
\end{array}\right)+\cdots+\left(\begin{array}{l}
n \\
2
\end{array}\right)\) = \(\left(\begin{array}{c}
n+1 \\
3
\end{array}\right)\)

First, recall Pascal’s identity

\(\left(\begin{array}{c}
r \\
s
\end{array}\right)+\left(\begin{array}{c}
r \\
s-1
\end{array}\right)=\left(\begin{array}{c}
r+1 \\
s
\end{array}\right), 1 \leq s \leq r\)

Proof by mathematical induction: for

for n=2, \(\left(\begin{array}{l}
2 \\
2
\end{array}\right)=1=\left(\begin{array}{c}
2+1 \\
3
\end{array}\right)=1\)

Thus its true for n=2. Now assume it’s true for n=k then prove it for n = k + 1. Let

\(\left(\begin{array}{l}
2 \\
2
\end{array}\right)+\cdots\left(\begin{array}{l}
k \\
2
\end{array}\right)=\left(\begin{array}{c}
k+1 \\
3
\end{array}\right)\)

Then

\(\left(\begin{array}{l}
2 \\
2
\end{array}\right)+\cdots\left(\begin{array}{l}
k \\
2
\end{array}\right)+\left(\begin{array}{c}
k+1 \\
3
\end{array}\right)\)

= \(\left(\begin{array}{c}
k+1 \\
3
\end{array}\right)+\left(\begin{array}{c}
k+1 \\
2
\end{array}\right)\)

= \(\left(\begin{array}{c}
k+2 \\
3
\end{array}\right)\)

(from Pascal’s identity)

Thus its true for n = k + 1, therefore by mathematical induction

\(\left(\begin{array}{l}
2 \\
2
\end{array}\right)+\cdots\left(\begin{array}{l}
n \\
2
\end{array}\right)=\left(\begin{array}{c}
n+1 \\
3
\end{array}\right) . \text { for } n \geq 2\)

We get, \(\left(\begin{array}{l}
2 \\
2
\end{array}\right)+\left(\begin{array}{l}
3 \\
2
\end{array}\right)+\left(\begin{array}{l}
4 \\
2
\end{array}\right)+\cdots+\left(\begin{array}{l}
n \\
2
\end{array}\right)\) = \(\left(\begin{array}{c}
n+1 \\
3
\end{array}\right)\)

From part (a), and the relation m2 = 2\(\left(\begin{array}{l}
m \\
2
\end{array}\right)\) + m for m ≥ 2,

We have to deduce the formula 12 + 22 + 32 +….+n2 = \(\frac{n(n+1)(2 n+1)}{6}\)

First we want to prove that m2 = 2\(\left(\begin{array}{l}
m \\
2
\end{array}\right)\) + m for m ≥ 2

2\(\left(\begin{array}{l}
m \\
2
\end{array}\right)\) + m <=> \(\frac{2 m !}{2 !(m-2) !}+m\) <=> m(m-1) + m = m2

Now we want to prove that:

12 + 22+ 32 +….+n2 = \(\frac{n(n+1)(2 n+1)}{6}\)

Proof:

12 + 22 + …. + n2

= \(1+2\left(\begin{array}{l}
2 \\
2
\end{array}\right)+2+2\left(\begin{array}{l}
3 \\
2
\end{array}\right)+3+\cdots+2\left(\begin{array}{l}
n \\
2
\end{array}\right)+n\)

= \((1+2+\cdots+n)+2\left[\left(\begin{array}{l}
2 \\
2
\end{array}\right)+\left(\begin{array}{l}
3 \\
2
\end{array}\right)+\cdots+\left(\begin{array}{l}
n \\
2
\end{array}\right)\right]\)

= \((n(n+1)] \frac{3+2 n-2}{6}\)

= \(\frac{n(n+1)}{2}+\frac{2(n+1) !}{3 !(n-2) !}\)

= \(\frac{n(n+1)}{2}+\frac{(n+1)(n)(n-1)}{3}\)

= \([n(n+1)]\left(\frac{1}{2}+\frac{n-1}{3}\right)\)

= \([n(n+1)] \frac{3+2 n-2}{6}\)

= \(\frac{n(n+1)(2 n+1)}{6}\)

We get, 12 + 22 + 32 +….+n2 = \(\frac{n(n+1)(2 n+1)}{6}\)

Here, we have to prove that 1.2 + 2.3 + …. + n(n+1) = \(\frac{n(n+1)(n+2)}{3}\)

Proof: from(b)

m2 = 2\(\left(\begin{array}{l}
m \\
2
\end{array}\right)\) + m ⇒ m(m-1) = 2\(\left(\begin{array}{l}
m \\
2
\end{array}\right)\), m ≥ 2

∴ 1.2 + 2.3 + …. + n.(n+1)

= \(2\left(\begin{array}{l}
2 \\
2
\end{array}\right)+2\left(\begin{array}{l}
3 \\
2
\end{array}\right)+\cdots+2\left(\begin{array}{l}
n \\
2
\end{array}\right)\)

= \(2\left[\left(\begin{array}{c}
n+2 \\
3
\end{array}\right)\right] \text { from (a) }\)

= \(2\left[\frac{(n+2) !}{3 !(n-1) !}\right]=\frac{2(n+2)(n+1)(n)}{3 \cdot 2 \cdot 1}\)

= \(\frac{n(n+1)(n+2)}{3}\)

Thus, we proved that 1.2 + 2.3 + …. + n(n+1) = \(\frac{n(n+1)(n+2)}{3}\)

 

David Burton Elementary Number Theory Solutions Chapter 1 Preliminaries Exercise 1.1 Page 12 Problem 6 Answer

Here, we have to derive the binomial identity,

\(\left(\begin{array}{l}
2 \\
2
\end{array}\right)+\left(\begin{array}{l}
4 \\
2
\end{array}\right)+\left(\begin{array}{l}
6 \\
2
\end{array}\right)+\cdots+\left(\begin{array}{c}
2 n \\
2
\end{array}\right)=\frac{n(n+1)(4 n-1)}{6} \quad n \geq 2\).

It’s given that m ≥ 2, \(\left(\begin{array}{c}
2 m \\
2
\end{array}\right)=2\left(\begin{array}{c}
m \\
2
\end{array}\right)+m^2\)

We can write as,

\(\left(\begin{array}{c}
2 m \\
2
\end{array}\right)=\frac{(2 m) !}{2 !(2 m-2) !}=\frac{(2 m)(2 m-1)}{2}=2 m^2-m=m^2+m^2-m=m^2+2\left(\begin{array}{c}
m \\
2
\end{array}\right) \mathrm{m} \geq 2 \text { from ex } 5 \text { (c) }\)

∴ \(\left(\begin{array}{l}
2 \\
2
\end{array}\right)+\left(\begin{array}{l}
4 \\
2
\end{array}\right)+\left(\begin{array}{l}
6 \\
2
\end{array}\right)+\cdots+\left(\begin{array}{c}
2 n \\
2
\end{array}\right)\)

= \(1+\left[2^2+2\left(\begin{array}{l}
2 \\
2
\end{array}\right)+\cdots+n^2+2\left(\begin{array}{l}
n \\
2
\end{array}\right)\right]\)

= \(\left(1^2+2^2+\cdots+n^2\right)+2\left[\left(\begin{array}{l}
2 \\
2
\end{array}\right)+\cdots+\left(\begin{array}{l}
n \\
2
\end{array}\right)\right]\)

= \(\frac{n(n+1)(2 n+1)}{6}+2\left(\begin{array}{c}
n+1 \\
3
\end{array}\right)\)

= \(\frac{n(n+1)(2 n+1)}{6}+\frac{2(n+1) !}{3 \cdot 3(n-2) !}\)

= \(\frac{n(n+1)(2 n+1)}{6}+\frac{6(n+1)(n)(n-1)}{6}\)

= \(\frac{n(n+1)[2 n+1+2 n-2]}{6}\)

= \(\frac{n(n+1)(4 n-1)}{6}\)

Thus, we derive the binomial identity,

\(\left(\begin{array}{l}
2 \\
2
\end{array}\right)+\left(\begin{array}{l}
4 \\
2
\end{array}\right)+\left(\begin{array}{l}
6 \\
2
\end{array}\right)+\cdots+\left(\begin{array}{c}
2 n \\
2
\end{array}\right)=\frac{n(n+1)(4 n-1)}{6} \quad n \geq 2\)

 

Page 12 Problem 7 Answer

Here, we have to verify that

12 + 32 + 52 + …. + (2n-1)2 = \(\left(\begin{array}{c}
2 n+1 \\
3
\end{array}\right)\)

We solve this by mathematical induction on n.

For the case n = 1, 12 = \(\left(\begin{array}{c}
3 \\
3
\end{array}\right)\) = 1

Assume that the identity is true for some k > 1.

For some k > 1,

12 + 32 + 52 + … + (2k−1)2 = \(\left(\begin{array}{c}
2 k+1 \\
3
\end{array}\right)\)

Add (2k+1)2 to both sides

L.H.S 12 + 32 + 52 + … + (2k-1)2 + (2k+1)2

R.H.S = \(\left(\begin{array}{c}
2 k+1 \\
3
\end{array}\right)\) + (2k+1)2

= \(\frac{(2 k+1)(2 k)(2 k-1)}{6}+(2 k+1)^2\)

= \((2 k+1)\left(\frac{(2 k)(2 k-1)}{6}+2 k+1\right)\)

= \((2 k+1)\left(\frac{4 k^2+10 k+6}{6}\right)\)

= \(\frac{(2 k+1)(2 k+2)(2 k+3)}{6}\)

= \(\left(\begin{array}{c}
2 k+1 \\
3
\end{array}\right)\)

Hence, the identity is true for k+1 too. This completes the induction. Hence, the identity is true for all integers greater than or equal to 1

12 + 32 + 52 + …. + (2k+1)2 = \(\left(\begin{array}{c}
2 k+1 \\
3
\end{array}\right)\)

Thus, we verified that

12 + 32 + 52 + …. + (2n-1)2 = \(\left(\begin{array}{c}
2 n+1 \\
3
\end{array}\right)\)

 

Burton Number Theory Exercise 1.1 Step-By-Step Solutions

David Burton Elementary Number Theory Solutions Chapter 1 Preliminaries Exercise 1.1 Page 12 Problem 8 Answer

Here, we have to show that for n ≥ 1,

\(\left(\begin{array}{c}
2 n \\
n
\end{array}\right)=\frac{1 \cdot 3 \cdot 5 \cdots(2 n-1)}{2 \cdot 4 \cdot 6 \cdots 2 n} 2^{2 n}\)

Expand the L.H.S according to definition,

\(\left(\begin{array}{c}
2 n \\
n
\end{array}\right)=\frac{1 \cdot 3 \cdot 5 \cdots(2 n-1)}{2 \cdot 4 \cdot 6 \cdots 2 n} 2^{2 n}\)

In the second step, cancel each (2n−2k) from the numerator by an(n−k) from the denominator. You get n 2′s in the numerator. Then multiply each term of the denominator by a 2 and multiply 2n to balance it out,

L.H.S = \(\left(\begin{array}{c}
2 n \\
n
\end{array}\right)=\frac{(2 n) !}{n ! n !}\)

= \frac{(2 n)(2 n-1) \cdots 2 \cdot 1}{n(n-1) \cdots 1 \cdot n(n-1) \cdots 1}

= \frac{(2 n-1)(2 n-3) \cdots \cdots 3 \cdot 1}{n(n-1) \cdots 1} 2^n

= \frac{(2 n-1)(2 n-3) \cdots \cdot 3 \cdot 1}{2 n(2 n-2) \cdots 2} 2^{2 n}

= \frac{1 \cdot 3 \cdot 5 \cdots(2 n-1)}{2 \cdot 4 \cdot 6 \cdots \cdots 2 n} 2^{2 n}

= R.H.S

Thus, we proved that for n ≥ 1,

\(\left(\begin{array}{c}
2 n \\
n
\end{array}\right)=\frac{1 \cdot 3 \cdot 5 \cdots(2 n-1)}{2 \cdot 4 \cdot 6 \cdots 2 n} 2^{2 n}\)

 

Page 12 Problem 9 Answer

Here, we have to show that x > y > z, hence x2 > xy > xz and establish the inequality \(2^n<\left(\begin{array}{c}
2 n \\
n
\end{array}\right)<2^{2 n}\), for n > 1. It’s given that x = 2.4.6…(2n), y = 1.3.5….(2n-1), and z = 1.2.3….n

Proof : We want to prove by induction that

n! < 1⋅3⋅5⋅⋅⋅⋅⋅(2n−1) for n > 1,for n = 2,2!<1⋅3, thus it’s true for n = 2. Now assume it’s true for n = k, let k! < 1⋅3⋅5⋅⋅⋅⋅(kn−1),then

(k+1)! = k!(k+1) < 1⋅3⋅5⋅⋅⋅⋅(kn−1)(k+1) < 1⋅3⋅5⋅⋅⋅⋅⋅(2k−1)(2k+1)

Note that: 2kk! = 2.4.6….2n-1

So,

2kk! < 1.3.5….(2k-1)2k

⇒ \(1<\frac{1 \cdot 3 \cdot 5 \cdots(2 k-1)}{2^k k !}\)

= \(\frac{1 \cdot 3 \cdot 5 \cdots(2 k-1)}{2 \cdot 4 \cdots 2 k !}\)

∴ \(2^k<\frac{1 \cdot 3 \cdot 5 \cdots(2 k-1)}{2 \cdot 4 \cdot 6 \cdots 2 k} 2^{2 k}=\left(\begin{array}{c}
2 k \\
k
\end{array}\right)\)

Now, since 2m−1 < 2m for m ≥ 1 for m ≥ 1,then 1⋅3⋅5⋯(2k−1)<2⋅4⋅6⋯2k

So, \(\frac{1 \cdot 3 \cdot 5 \cdots(2 k-1)}{2 \cdot 4 \cdot 6 \cdots 2 k}\), for k ≥ 1

Therefore, by ex (8),

\(\left(\begin{array}{c}
2 k \\
k
\end{array}\right)=\frac{1 \cdot 3 \cdot 5 \cdots(2 k-1)}{2 \cdot 4 \cdot 6 \cdots 2 k} 2^{2 k}<2^{2 k}, n \geq 1\)

Thus, we establish the equality \(2^n<\left(\begin{array}{c}
2 n \\
n
\end{array}\right)<2^{2 n}\), for n > 1

 

Page 12 Problem 10 Answer

Here, we have to prove that Cn can be given inductively by Cn = \(\frac{2(2 n-1)}{n+1} C_{n-1}\). It’s given that Catalan numbers, defined by

\(C_n=\frac{1}{n+1}\left(\begin{array}{c}
2 n \\
n
\end{array}\right)=\frac{(2 n) !}{n !(n+1) !} \quad n=0,1,2, \ldots\) from the sequence 1, 1, 2, 5, 14, 42, 132, 429, 1430, 4862,…

Multiply by 2n in the numerator and the denominator,

\(\frac{2(2 n-1)}{n+1} C_{n-1}=\frac{2(2 n-1)}{n+1} \frac{(2 n-2) !}{(n-1) !(n) !}\)

= \(\frac{2(2 n-1) !}{(n+1) !(n-1) !}\)

= \(\frac{2(2 n)(2 n-1) !}{2(n+1) ! n(n-1) !}\)

= \(\frac{(2 n) !}{(n+1) ! n !}\)

= Cn

Thus, we proved that Cn can be inductively by Cn = \(\frac{2(2 n-1)}{n+1} C_{n-1}\)

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials

Page 21 Exercise 3 Answer

Question: Find the factors of the second-order degree polynomial x2 − 17x + 16?

Solution:

Given: x2 − 17x + 16

To find: factorize each into a product of two binomials.

Given that x2 − 17x + 16

First factorizing as 16 many different ways we can -16x-1,-8x-2,- 4x-4

While testing the combination -16x-1

So,

⇒ \(\begin{aligned}
& x^2-17 x+16 \\
\Rightarrow & x^2-x-16 x+16 \\
\Rightarrow & x(x-1)-16(x-1) \\
\Rightarrow & (x-1)(x-16)
\end{aligned}\)

Finally x2-17x+16=(x-1)(-16)

Thus, the factorization of the second degree polynomial x2 − 17x + 16 into a product of two binomials is (x−1)(x−16)

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2

Page 21 Exercise 4 Answer

Question: Find the factors of the second-order degree polynomial x2 − 8x + 15?

Solution:

Given: x2 − 8x + 15

To find: factorize each into a product of binomials.

Given that x²-18x+15

First factorizing 15 as many different ways

We can -15x-1,-3x-5

While testing the combinations, 3x-5

So, x²-8x+15

⇒ \(\begin{aligned}
& \Rightarrow x^2-5 x-3 x+15 \\
& \Rightarrow x(x-5)-3(x-5) \\
& \Rightarrow(x-3)(x-5)
\end{aligned}\)

Finally, x²-8x+15=(x-3)(x-5)

Thus, the factorization of the second degree polynomial x2 − 8x + 15 into a product of two binomials is (x−3)(x−5)

Question: Find the factors of the second-order degree polynomial x2 − 16x + 15?

Solution:

Page 21 Exercise 5 Answer

Given: x2 − 16x + 15

To find: factorize each into a product of two binomials.

Given that x2-16x+15

First factorizing 15 as many different ways

We can -15x-1,-3x-5

while testing the combinations, -3x-5

So x2-8x+15

⇒ x2-5x-3x+15
⇒ x(x-5)-3(x-5)
⇒ (x-3)(x-5)

Finally, x2-8x+15=(x-3)(x-5)

Thus, the factorization of second degree polynomial x2 − 16x + 15 into a product of two binomials is (x−1)(x−5)

Mcgraw Hill Key To Algebra Book 4 Chapter 8 Part 2 Solutions

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 21 Exercise 6 Answer

Question: Find the factors of the second-order degree polynomial x2 − 17x + 72?

Solution:

Given: x2 − 17x + 72

To find: factorize each into a product of two binomials.

Given that x2-17x+72

First factorizing 72 as many different ways

we can -36x-2,-24x-3,-9x-8

while testing the combinations, -9x-8

so x²-17x+72

⇒ \(\begin{aligned}
& \Rightarrow x^2-9 x-8 x+72 \\
& \Rightarrow x(x-9)-8(x-9) \\
& \Rightarrow(x-8)(x-9)
\end{aligned}\)

Finally, x2-17x+72=(x-9)(x-8)

Thus, the factorization of second degree polynomial x2 − 17x + 72 into a product of two binomials is (x−9)(x−8)

Page 21 Exercise 8 Answer

Question: Find the factors of the polynomial x2 + 3x − 28?

Solution:

Given: x2 + 3x − 28

To find: factorize each into a product of two binomials.

Given that x2+3x-28
First factorising 28 as many different ways

we can 14x-2,7x-4

while testing the combinations, 7x-4

So, x2+3x-28

⇒ \(\begin{aligned}
& \Rightarrow x^2-7 x+4 x-28 \\
& \Rightarrow x(x-7)+4(x-7) \\
& \Rightarrow(x+4)(x-7)
\end{aligned}\)

Finally, x²+3x-28=(x+4)(X-7)

So. the factorization of second-degree polynomial x2 + 3x − 28 = (x+7)(x−4) is a product of two binomials.

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 21 Exercise 9 Answer

Question: Find the factors of the polynomial x2 − 2x − 24?

Solution:

Given: x2 − 2x − 24

To find: factorize each into the product of two binomials.

Given that x²-2x-24

first factorizing 24 as many different ways

we can -24×1, -12×2,-6×4

So, x²-2x-24

⇒ \(\begin{aligned}
& \Rightarrow x^2-6 x+4 x-24 \\
& \Rightarrow x(x-6)+4(x-6) \\
& \Rightarrow(x+4)(x-6)
\end{aligned}\)

Finally, x2-2x-24=(x-6)(x+4)

Thus, factorization of second degree polynomial x2 − 2x − 24 = (x−6)(x+4) is a product of two binomials.

Page 21 Exercise 10 Answer

Question: Find the factors of the polynomial x2 − 2x − 24?

Solution:

We have been given a polynomial x2 + 2x − 24 and we have to factorize it.

Given polynomial: x²+2x-24

\(\begin{aligned}
x^2+2 x-24 & =x^2+6 x-4 x-24 \\
& =x(x+6)-4(x+6) \\
& =(x-4)(x+6)
\end{aligned}\)

The factors of the polynomial x2 + 2x − 24 are (x−4) and (x+6)

Page 21 Exercise 11 Answer

Question: Find the factors of the polynomial x2 + 8x − 20?

Solution:

We have been given a polynomial x2 + 8x − 20 and we have to factorize it.

Given polynomial: x²-8x-20

⇒ \(\begin{aligned}
x^2-8 x-20 & =x^2-10 x+2 x-20 \\
& =x(x-10)+2(x-10) \\
& =(x+2)(x-10)
\end{aligned}\)

The polynomial x2 + 8x – 20 are (x-2) and (x+10)

Page 21 Exercise 12 Answer

Question: Find the factors of the polynomial x2 + 8x − 20?

Solution:

We have been given a polynomial x2 − 8x − 20 and we have to factorize it.

Given polynomial: x²+8x-20

⇒ \(\begin{aligned}
x^2+8 x-20 & =x^2+10 x-2 x-20 \\
& =x(x+10)-2(x+10) \\
& =(x-2)(x+10)
\end{aligned}\)

The factors of the polynomial x2 − 8x − 20 are (x+2) and (x−10)

Page 21 Exercise 1 Answer

Question: Find the factors of the polynomial x2 − 16?

Solution:

We have been given a polynomial x2 − 16 and we have to factorize it.

Given polynomial: x2-16

x²-16=x²-4²

=(x+4)(x-4)

[since (a²-b²) = (a+b)(a-b)]

The factors of the polynomial x2 – 16 are (x+4) and (x-4).

Key To Algebra Book 4 Multiplying And Factoring Polynomials Part 2 Answers

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 21 Exercise 2 Answer

Question: Find the factors of the polynomial x2 − 25?

Solution:

We have been given a polynomial x2 − 25 and we have to factorize it.

Given polynomial: x2-25

x²-25=x²-5²

=(x+5)(x-5)

[since (a²-b²) = (a+b)(a-b)]

The factors of the polynomial x2 – 25 are (x-5) and (x+5).

Page 21 Exercise 3 Answer

Question: Find the factors of the polynomial x2 − 81?

Solution:

We have been given a polynomial x2 − 81 and we have to factorize it.

Given polynomial: x2-81

x²-81=x²-9²

=(x+9)(x-9)

[since (a²-b²) = (a+b)(a-b)]

The factors of the polynomial x2 – 81 are (x+9) and (x-9).

Page 21 Exercise 4 Answer

Question: Find the factors of the polynomial x2 − 4?

Solution:

We have been given a polynomial x2 − 4 and we have to factorize it.

Given polynomial: x2-4

x²-4=x²-2²

=(x+2)(x-2)

[since (a²-b²) = (a+b)(a-b)]

The factors of the polynomial x2 – 4 are (x+2) and (x-2).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 21 Exercise 5 Answer

Question: Find the factors of the polynomial x2 − 1?

Solution:

We have been given a polynomial x2 − 1 and we have to factorize it.

Given polynomial: x2-1

x²-1=x²-1²

=(x+1)(x-1)

[since (a²-b²) = (a+b)(a-b)]

The factors of the polynomial x2 – 1 are (x+1) and (x-1).

Page 21 Exercise 6 Answer

Question: Find the factors of the polynomial x2 − 100?

Solution:

We have been given a polynomial x2 − 100 and we have to factorize it.

Consider that:

Given polynomial: x2-100

Consider that:

A²-b²=(a+b)(a-b)
x²-100=x²-10²
=(x+10)(x-10)

[since (a²-b²) = (a+b)(a-b)]

The factors of the polynomial x2 − 100 are (x+10) and (x−10).

Page 22 Exercise 2 Answer

Question: Find the factors of the polynomial x2 − 4x − 45?

Solution:

The given polynomial is x2 − 4x − 45.

The objective is to find the factor of the given polynomial.

The given polynomial is x²-4x-45

⇒ \(\begin{aligned}
x^2-4 x-45 & =x^2-(9-5) x-45 \\
& =x^2-9 x+5 x-45 \\
& =x(x-9)+5(x-9) \\
& =(x+5)(x+9)
\end{aligned}\)

Hence, the factor of the polynomial, x2 − 4x − 45 is (x+5)(x−9).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 22 Exercise 3 Answer

Question: Find the factors of the polynomial x2 + 18x + 45?

Solution:

The given polynomial is x2 + 18x + 45.

The objective is to find the factor of the given polynomial.

The given polynomial x²+18x+45

The polynomial,

x²+18x+45= x²+(15+3)x+45

=x²+15x+3x+45

=x(X+15)+3(x+15)

=(X+3)(x+15)

Now, check the answer

(x+3)(x+15)=x²+15x+3x+45

=x²+18x+45

Hence, the factor of the polynomial, x2 + 18x + 45 is (x+3)(x+15).

Page 22 Exercise 4 Answer

Question: Find the factors of the polynomial x2 − 12x − 45?

Solution:

The given polynomial is x2 − 12x − 45.

The objective is to find the factor of the given polynomial.

The given polynomial is x2-12x-45

The polynomial

x²-12x-45= x2-(15-3)x-45
=x2-15x+3x-45
=x(x-15)+3(x-15)

Now, check the answer

(x+3)(x-15)=x2-15x+3x-45
=x²-12x-45

Hence, the factor of the polynomial, x2 – 12x – 45 is (x+3)(x-15).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 22 Exercise 5 Answer

Question: Find the factors of the polynomial x2 − 14x + 45?

Solution:

The given polynomial is x2 − 14x + 45.

The objective is to find the factor of the given polynomial.

The given polynomial is 2-14x+45

The polynomial,

⇒ \(\begin{aligned}
x^2-14 x+45 & =x^2-(9+5) x+45 \\
& =x^2-9 x-5 x+45 \\
& =x(x-9)-5(x-9) \\
& =(x-5)(x-9)
\end{aligned}\)

Now, check the answer

⇒ \(\begin{aligned}
(x-5)(x-9) & =x^2-9 x-5 x+45 \\
& =x^2-14 x+45
\end{aligned}\)

Hence, the factor of the polynomial, x2 − 14x + 45 is (x−5)(x−9).

Page 22 Exercise 6 Answer

Question: Find the factors of the polynomial x2 + 12x − 45?

Solution:

The given polynomial is x2 + 12x − 45.

The objective is to find the factor of the given polynomial.

The given polynomial is  x²+12x-45

The polynomial,

⇒ \(\begin{aligned}
x^2+12 x-45 & =x^2+(15-3) x-45 \\
& =x^2+15 x-3 x-45 \\
& =x(x+15)-3(x+15) \\
& =(x-3)(x+15)
\end{aligned}\)

Now, check the answer

⇒ \(\begin{aligned}
(x-3)(x+15) & =x^2+15 x-3 x-45 \\
& =x^2+12 x-45
\end{aligned}\)

Hence, the factor of the polynomial, x2 + 12x − 45 is (x−3)(x+15).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 22 Exercise 7 Answer

Question: Find the factors of the polynomial x2 + 4x − 45?

Solution:

The given polynomial is x2 + 4x − 45.

The objective is to find the factor of the given polynomial.

The given polynomial is x²+4x-45

The polynomial

⇒ \(\begin{aligned}
x^2+4 x-45 & =x^2+(9-5) x-45 \\
& =x^2+9 x-5 x-45 \\
& =x(x+9)-5(x+9) \\
& =(x-5)(x+9)
\end{aligned}\)

Now,  check the answer

⇒ \(\begin{aligned}
(x-5)(x+9) & =x^2+9 x-5 x-45 \\
& =x^2+4 x-45
\end{aligned}\)

Hence, the factor of the polynomial, x2 + 4x − 45 is (x−5)(x+9).

Page 22 Exercise 8 Answer

Question: Find the factors of the polynomial x2 − 18x + 45?

Solution:

The given polynomial is x2 − 18x + 45.

The objective is to find the factor of the given polynomial.

The given polynomial is x²-18x+45

The polynomial,

⇒ \(\begin{aligned}
x^2-18 x+45 & =x^2-(15+3) x+45 \\
& =x^2-15 x-3 x+45 \\
& =x(x-15)-3(x-15) \\
& =(x-3)(x-15)
\end{aligned}\)

Now, check the answer

⇒ \(\begin{aligned}
(x-3)(x-15) & =x^2-15 x-3 x+45 \\
& =x^2-18 x+45
\end{aligned}\)

Hence, the factor of the polynomial, x2 − 18x + 45 is (x−3)(x−15).

Page 22 Exercise 10 Answer

Question: Find the factors of the polynomial x2 − 44x − 45?

Solution:

The given polynomial is x2 − 44x − 45.

The objective is to find the factor of the given polynomial.

The given polynomial is x²-44x-45

The polynomial

⇒ \(\begin{aligned}
x^2-44 x-45 & =x^2-(45-1) x-45 \\
& =x^2-45 x+x-45 \\
& =x(x-45)+1(x-45) \\
& =(x+1)(x-45)
\end{aligned}\)

Now, check the answer

(x+1)(x-45)=x²-45x+x-45

=x²-44x-45

Hence, the factor of the polynomial, x2 − 44x − 45 is (x+1)(x−45).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 22 Exercise 11 Answer

Question: Find the factors of the polynomial x2 + 44x − 45?

Solution:

The given polynomial is x2 + 44x − 45.

The objective is to find the factor of the given polynomial.

The given polynomial is x²+44x-45 the polynomial,

⇒ \(\begin{aligned}
x^2+44 x-45 & =x^2+(45-1) x-45 \\
& =x^2+45 x-x-45 \\
& =x(x+45)-(x+45) \\
& =(x-1)(x+45)
\end{aligned}\)

Now, check the answer

⇒ \(\begin{aligned}
(x-1)(x+45) & =x^2+45 x-x+45 \\
& =x^2+44 x-45
\end{aligned}\)

Hence, the factor of the polynomial, x2 + 44x − 45 is (x−1)(x+45).

Page 22 Exercise 12 Answer

Question: Find the factors of the polynomial x2 − 46x + 45?

Solution:

The given polynomial is x2 − 46x + 45.

The objective is to find the factor of the given polynomial.

The polynomial

⇒ \(\begin{aligned}
x^2-46 x+45 & =x^2-(45+1) x+45 \\
& =x^2-45 x-x+45 \\
& =x(x-45)-1(x-45) \\
& =(x-1)(x-45)
\end{aligned}\)

Now, check the answer

⇒ \(\begin{aligned}
(x-1)(x-45) & =x^2-45 x-x+45 \\
& =x^2-46 x+45
\end{aligned}\)

Hence, the factor of the polynomial, x2 − 46x + 45 is (x−1)(x−45).

Page 22 Exercise 13 Answer

Question: Find the factors of the polynomial a2 + 17a + 72?

Solution:

The given polynomial is a2 + 17a + 72.

The objective is to find the factor of the given polynomial.

The polynomial,

⇒ \(\begin{aligned}
a^2+17 a+72 & =a^2+(8+9) a+72 \\
& =a^2+8 a+9 a+72 \\
& =a(a+8)+9(a+8) \\
& =(a+8)(a+9)
\end{aligned}\)

Now, check the answer

(a+8)(a+9)=a²+9a+8a+72
=a²+17a+72

Hence, the factor of the polynomial, a2 + 17a + 72 is (a+8)(a+9).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 22 Exercise 14 Answer

Question: Find the factors of the polynomial a2 − a − 72?

Solution:

The given polynomial is a2 − a − 72.

The objective is to find the factor of the given polynomial.

⇒ \(\begin{aligned}
a^2-a-72 & =a^2-(9-8) a-+2 \\
& =a^2-9 a+8 a-72 \\
& =a(a-9)+8(a-9) \\
& =(a+8)(a-9)
\end{aligned}\)

Now, check the answer

⇒ \(\begin{aligned}
(a+8)(a-a) & =a^2-9 a+8 a-72 \\
& =a^2-a-72
\end{aligned}\)

Hence, the factor of the polynomial, a2 − a − 72 is (a+8)(a−9).

Page 22 Exercise 16 Answer

Question: Find the factors of the polynomial x2 − 5x + 4?

Solution:

The given polynomial is x2 − 5x + 4.

The objective is to find the factor of the given polynomial.

⇒ \(\begin{aligned}
x^2-5 x+4 & =x^2-(4+1) x+4 \\
& =x^2-4 x-x+4 \\
& =x(x-4)-(x-4) \\
& =(x-1)(x-4)
\end{aligned}\)

Now, check the answer

⇒ \(\begin{aligned}
(x-1)(x-4) & =x^2-4 x-x+4 \\
& =x^2-5 x+4
\end{aligned}\)

Hence, the factor of the polynomial, x2 − 5x + 4 is (x−1)(x−4).

Page 22 Exercise 17 Answer

Question: Find the factors of the polynomial x2 + 3x − 4?

Solution:

The given polynomial is x2 + 3x − 4.

The objective is to find the factor of the given polynomial.

⇒ \(\begin{aligned}
x^2-5 x+4 & =x^2-(4+1) x+4 \\
& =x^2-4 x-x+4 \\
& =x(x-4)-(x-4) \\
& =(x-1)(x-4)
\end{aligned}\)

Hence, the factor of the polynomial, x2 + 3x − 4 is (x−1)(x+4).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 22 Exercise 18 Answer

Question: Find the factors of the polynomial x2 + 4x − 12?

Solution:

The given polynomial is x2 + 4x − 12.

The objective is to find the factor of the given polynomial.

The Given polynomial x²+4x-12 the polynomial,

⇒ \(\begin{aligned}
x^2+4 x-12 & =x^2+(6-2) x-12 \\
& =x^2+6 x-2 x-12 \\
& =x(x+6)-2(x+6) \\
& =(x-2)(x+6)
\end{aligned}\)

Now check the answer

⇒ \(\begin{aligned}
(x-2)(x+6) & =x^2+6 x-2 x-12 \\
& =x^2+4 x-12
\end{aligned}\)

Hence, the factor of the polynomial, x2 + 4x − 12 is (x−2)(x+6).

Page 22 Exercise 19 Answer

Question: Find the factors of the polynomial x2 − 4x + 4?

Solution:

The given polynomial is x2 − 4x + 4.

The objective is to find the factor of the given polynomial.

The given polynomial is  x2-4x+4

⇒ \(\begin{aligned}
x^2-4 x+4 & =x^2-(2+2) x+4 \\
& =x^2-2 x-2 x+4 \\
& =x(x-2)-2(x-2) \\
& =(x-2)(x-2) \\
& =(x-2)^2
\end{aligned}\)

Hence, the factor of the polynomial, x2 − 4x + 4 is (x−2)2.

Page 22 Exercise 20 Answer

Question: Find the factors of the polynomial s2 − 10s + 25?

Solution:

The given polynomial is s2 − 10s + 25.

The objective is to find the factor of the given polynomial.

The given polynomial is s2-10s+25

The polynomial,

⇒ \(\begin{aligned}
s^2-10 s+25 & =s^2-(5+s) s+25 \\
& =s^2-5 s-5 s+25 \\
& =s(s-5)-5(s-5) \\
& =(s-5)(s-5) \\
& =(s-5)^2
\end{aligned}\)

Now, check the answer

(s-5)²=s³-10s+25

[since (a-b)²=a²-2ab+b²]

Hence, the factor of the polynomial, s2 − 10s + 25 is (s−5)2.

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 22 Exercise 21 Answer

Question: Find the factors of the polynomial y2 − 6y + 9?

Solution:

The given polynomial is y2 − 6y + 9.

The objective is to find the factor of the given polynomial.

The given polynomial is y²-6y+9

The poynomial

⇒ \(\begin{aligned}
y^2-6 y+9 & =y^2-(3+3) y+9 \\
& =y^2-3 y-3 y+9 \\
& =y(y-3)-3(y-3) \\
& =(y-3)(y-3) \\
& =(y-3)^2
\end{aligned}\)

Now, check the answer

(y-3)²=y²-6y+9
[since(a-b)²=a²-2ab+b²]

Hence, the factor of the polynomial, y2 − 6y + 9 is (y−3)2.

Page 22 Exercise 22 Answer

Question: Find the factors of the polynomial a2 + 2a + 1?

Solution:

The given polynomial is a2 + 2a + 1.

The objective is to find the factor of the given polynomial.

The given polynomial is a²+2a+1

The polynomial,

⇒ \(\begin{aligned}
a^2+2 a+1 & =a^2+(1+1) a+1 \\
& =a^2+a+a+1 \\
& =a(a+1)+(a+1) \\
& =(a+1)(a+1) \\
& =(a+1)^2
\end{aligned}\)

Now, check the answer

(a+1)²=a2+2a+1
(since (a+b)²=a²+2ab+b²]

Hence, the factor of the polynomial, a2 + 2a + 1 is (a+1)2.

Page 22 Exercise 24 Answer

Question: Find the factors of the polynomial c2 − c − 2?

Solution:

The given polynomial is c2 − c − 2.

The objective is to find the factor of the given polynomial.

⇒ \(\begin{aligned}
c^2-c-2 & =c^2-(2-1) c-2 \\
& =c^2-2 c+c-2 \\
& =c(c-2)+1(c-2) \\
& =(c+1)(c-2)
\end{aligned}\)

Now, check the answer

⇒ \(\begin{aligned}
(c+1)(c-2) & =c^2-2 c+c-2 \\
& =c^2-c-2
\end{aligned}\)

Hence, the factor of the polynomial, c2 − c − 2 is (c+1)(c−2).

Mcgraw Hill Multiplying And Factoring Part 2 Solutions Chapter 8 Key To Algebra

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 23 Exercise 1 Answer

Question: Find the factors of the polynomial b2 + 4b − 60?

Solution:

Given:

The given equation is b2 + 4b − 60.

To find:

The objective is to compute the factor of the given polynomial.

The given eqaution is b2+4b-60

Factorizing the above eqaution

b²+4b-60

⇒ \(\begin{aligned}
& =b^2+(10-6) b-60 \text {; (by middle term factor) } \\
& =b^2+10 b-6 b-60 \\
& =\left(b^2+10 b\right)-(6 b+60) \\
& =b(b+10)-6(b+10) \\
& =(b+10)(b-6)
\end{aligned}\)

The required factorization of the second-degree polynomial is b2 + 4b − 60 = (b+10)(b−6).

Page 23 Exercise 2 Answer

Question: Find the factors of the polynomial a2 − 3a − 28?

Solution:

Given:

The given equation is a2 − 3a − 28

To find:

The objective is to compute the factor of the given polynomial.

The given eqaution is a²-3a-28

Factorizing the abve eqaution

a²-3a-28

⇒ \(\begin{aligned}
& =a^2-(7-4) a-28 ; \text { (by middle term factor) } \\
& =a^2-7 a+4 a-28 \\
& =\left(a^2-3 a\right)+(4 a-28) \\
& =a(a-7)+4(a-7) \\
& =(a-7)(a+4)
\end{aligned}\)

The required factorization of the second-degree polynomial is a2 − 3a − 28 = (a−7)(a+4).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 23 Exercise 3 Answer

Question: Find the factors of the polynomial m2 − 2m − 63?

Solution:

Given:

The given equation is m2 − 2m − 63.

To find:

The objective is to compute the factor of the given polynomial.

The given equation is m²-2m-6³
factorizing the above equation
m²-2m-63

⇒ \(\begin{aligned}
& =m^2-(9-7) m-63 \text {; (by middle term factor) } \\
& =m^2-9 m+7 m-63 \\
& =\left(m^2-9 m\right)+(7 m-63) \\
& =m(m-9)+7(m-9) \\
& =(m-9)(m+7)
\end{aligned}\)

The required factorization of the second-degree polynomial is m2 − 2m − 63 = (m−9)(m+7).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 23 Exercise 4 Answer

Question: Find the factors of the polynomial x2 − 7x − 18?

Solution:

Given:

The given equation is x2 − 7x − 18.

To find:

The objective is to compute the factor of the given polynomial.

The polynomial

⇒ \(\begin{aligned}
x^2-12 x-45 & =x^2-(15-3) x-45 \\
& =x^2-15 x+3 x-45 \\
& =x(x-15)+3(x-15) \\
& =(x+3)(x-15)
\end{aligned}\)

Now, check the answer

⇒ \(\begin{aligned}
(x+3)(x-15) & =x^2-15 x+3 x-45 \\
& =x^2-12 x-45
\end{aligned}\)

The required factorization of the second-degree polynomial is x2 − 7x − 18 = (x−9)(x+2).

Page 23 Exercise 6 Answer

Question: Find the factors of the polynomial a2 − a − 20?

Solution:

Given:

The given equation is a2 − a − 20.

To find:

The objective is to compute the factor of the given polynomial.

The  given equation a²-a-20

Factorizing the above equation

a²-a-20
=a2-(5-4)a-20;(by middle term factor)

⇒ \(\begin{aligned}
& =a^2-5 a+4 a-20 \\
& =\left(a^2-5 a\right)+(4 a-20) \\
& =a(a-5)+4(a-5) \\
& =(a-5)(a+4)
\end{aligned}\)

The required factorization of the second-degree polynomial is a2 − a − 20 = (a−5)(a+4).

Page 23 Exercise 8 Answer

Question: Find the factors of the polynomial z2 + z − 12?

Solution:

Given:

The given equation is z2 + z − 12.

To find:

The objective is to compute the factor of the given polynomial.

The given equation is x2+x-12

Factorizing the above equation,

z²+z-12

⇒ \(\begin{aligned}
& =z^2+(4-3) z-12 ; \text { (by middle term factor) } \\
& =z^2+4 z-3 z-12 \\
& =\left(z^2+4 z\right)-(3 z+12) \\
& =z(z+4)-3(z+4) \\
& =(z-3)(z+4)
\end{aligned}\)

The required factorization of the second-degree polynomial is z2 + z − 12 = (z+4)(z−3).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 23 Exercise 11 Answer

Question: Find the factors of the polynomial x2 − 2x − 3?

Solution:

Given:

The given equation is x2 − 2x − 3.

To find:

The objective is to compute the factor of the given polynomial.

The given equation is x²-2x-3

Factorizing the above equation

⇒ \(\begin{aligned}
& x^2-2 x-3 \\
&= x^2-(3-1) x-3 ; \text { (by middle term factor) } \\
&= x^2-3 x+x-3 \\
&=\left(x^2-3 x\right)+(x-3) \\
&= x(x-3)+1(x-3) \\
&=(x+1)(x-3)
\end{aligned}\)

The required factorization of the second-degree polynomial is x2 − 2x − 3 = (x−3)(x+1).

Page 23 Exercise 12 Answer

Question: Find the factors of the polynomial x2 + 2x − 3?

Solution:

Given:

The given equation is x2 + 2x − 3.

To find:

The objective is to compute the factor of the given polynomial.

The given eqaution is x²-2x-3

Factorizing the above eqaution

⇒ \(\begin{aligned}
& x^2+2 x-3 \\
&= x^2+(3-1) x-3 ; \text { (by midd le term factor) } \\
&= x^2+3 x-x-3 \\
&=\left(x^2+3 x\right)-1(x+3) \\
&= x(x+3)-1(x+3) \\
&=(x-1)(x+3)
\end{aligned}\)

The required factorization of the second-degree polynomial is x2 + 2x − 3 = (x+3)(x−1).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 23 Exercise 14 Answer

Question: Find the factors of the polynomial x2 − 8x + 12?

Solution:

Given:

The given equation is x2 − 8x + 12.

To find:

The objective is to compute the factor of the given polynomial.

The given equation is x2 − 8x + 12.

Factorizing the above eqaution

⇒ \(\begin{aligned}
& x^2-8 x+12 \\
= & x^2-(6+2) x+12 \text {; (by middle term factor) } \\
= & x^2-6 x-2 x+12 \\
= & x(x-6)-2(x-6) \\
= & (x-2)(x-6)
\end{aligned}\)

The required factorization of the second-degree polynomial is x2 − 8x + 12 = (x−6)(x−2).

Page 23 Exercise 15 Answer

Question: Find the factors of the polynomial x2 − 9x + 8?

Solution:

Given:

The given equation is x2 − 9x + 8.

To find:

The objective is to compute the factor of the given polynomial.

The given equation is x2 − 9x + 8.

Factorizing the above eqaution,

⇒ \(\begin{aligned}
& x^2-9 x+8 \\
= & x^2-(8+1) x+8 \text {; (by middle term factor) } \\
= & x^2-8 x-x+8 \\
= & \left(x^2-8 x\right)-1(x-8) \\
= & x(x-8)-1(x-8) \\
= & (x-1)(x-8)
\end{aligned}\)

The required factorization of the second-degree polynomial is x2 − 9x + 8 = (x−8)(x−1).

Page 23 Exercise 16 Answer

Question: Find the factors of the polynomial s2 + 13s + 42?

Solution:

Given:

The given equation is s2 + 13s + 42.

To find:

The objective is to compute the factor of the given polynomial.

The given polynomial is s2 + 13s + 42.

The polynomial,

⇒ \(\begin{aligned}
x^2-5 x+4 & =x^2-(4+1) x+4 \\
& =x^2-4 x-x+4 \\
& =x(x-4)-(x-4) \\
& =(x-1)(x-4)
\end{aligned}\)

Now, check the answer

⇒ \(\begin{aligned}
(x-1)(x-4) & =x^2-4 x-x+4 \\
& =x^2-5 x+4
\end{aligned}\)

The required factorization of the second degree polynomial is s2 + 13s + 42 = (s+7)(s+6)

Chapter 8 Part 2 Multiplying And Factoring Polynomials Mcgraw Hill Key

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 23 Exercise 17 Answer

Question: Find the factors of the polynomial x2 − 14x + 48?

Solution:

Given:

The given equation is x2 − 14x + 48.

To find:

The objective is to compute the factor of the given polynomial.

The given equation is x2-14x+48

Factorizing the above equation,

⇒ \(\begin{aligned}
& x^2-14 x+48 \\
= & x^2-(6+8) x+48 ; \text { (by middle term factor) } \\
= & x^2-6 x-8 x+48 \\
= & \left(x^2-6 x\right)-8(x-6) \\
= & x(x-6)-8(x-6) \\
= & (x-6)(x-8)
\end{aligned}\)

The required factorization of the second-degree polynomial is x2 − 14x + 48 = (x−6)(x−8).

Page 23 Exercise 18 Answer

Question: Find the factors of the polynomial x2 − 9?

Solution:

Given:

The given equation is x2 − 9.

To find:

The objective is to compute the factor of the given polynomial.

The given equation is x²-9

factorizing the above equation,

x²-9

=(x)²-(3)², using the identify

a²-b²=(a+b)(a-b)

=(x+3)(x-3)

The required factorization of the second-degree polynomial is x2 − 9 = (x+3)(x−3).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 23 Exercise 19 Answer

Question: Find the factors of the polynomial a2 − 36?

Solution:

Given:

The given equation is a2 − 36

To find:

The objective is to compute the factor of the given polynomial.

The given equation is a²-36

=(a)²-(6)²

=(a+6)(a-6) using the identity

a²-b²=(a+b)(a-b)

The required factorization of the second-degree polynomial is a2 − 36 = (a+6)(a−6).

Page 23 Exercise 20 Answer

Question: Find the factors of the polynomial y2 − 64?

Solution:

Given:

The given equation is y2 − 64.

To find:

The objective is to compute the factor of the given polynomial.

The given eqaution is y²-64

Factorizing the above eqaution

y²-64

=(y)²-(8)²

=(y+8)(y-8) using the identity

a²-b²=(a+b)(a-b)

The required factorization of the second-degree polynomial is y2 − 64 = (y+8)(y−8).

Page 23 Exercise 21 Answer

Question: Find the factors of the polynomial x2 − 1?

Solution:

Given:

The given equation is x2 − 1.

To find:

The objective is to compute the factor of the given polynomial.

The given equation is x2 − 1.

Factorizing the above eqaution,

⇒ \(\begin{aligned}
& x^2-1 \\
&=(x)^2-(1)^2 \\
&=(x+1)(x-1) \text { using the identity } \\
& a^2-b^2=(a+b)(a-b)
\end{aligned}\)

The required factorization of the second-degree polynomial is x2 − 1 = (x+1)(x−1).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 23 Exercise 22 Answer

Question: Find the factors of the polynomial x2 − 49?

Solution:

Given:

The given equation is x2 − 49.

To find:

The objective is to compute the factor of the given polynomial.

The given eqaution is x²-49

factorizing the above eqautioon

⇒ \(\begin{aligned}
& x^2-49 \\
&=(x)^2-(7)^2 \\
&=(x+7)(x-7) \text { using the identity } \\
& a^2-b^2=(a+b)(a-b)
\end{aligned}\)

The required factorization of the second-degree polynomial is x2 − 49 = (x+7)(x−7).

Page 23 Exercise 23 Answer

Question: Find the factors of the polynomial x2 − 16?

Solution:

Given:

The given equation is x2 − 16.

To find:

The objective is to compute the factor of the given polynomial.

The gioven eqaution is x²-16

factorizing the above eqaution

⇒ \(\begin{aligned}
& x^2-16 \\
= & x^2-(4)^2 \\
= & (x+4)(x-4) \text { using the identity } \\
\Leftrightarrow & \left.a^2-b^2=(a+b)(a-b)\right]
\end{aligned}\)

The required factorization of the second-degree polynomial x2 − 16 = (x+4)(x−4).

Page 24 Exercise 2 Answer

Question: Find the Product Of The Expression 4(x−3)(x+5)?

Solution:

We have been given an expression 4(x−3)(x+5).

We have to multiply the given monomial with the given binomials.

We will find the result by multiplying the binomials first and then multiplying it with the monomial.

The given expression is 4(x-3)(x+5) Multiplying the binomial we get,

⇒ \(\begin{aligned}
4(x-3)(x+5) & =4\left(x^2-3 x+5 x-15\right) \\
& =4\left(x^2+2 x-15\right)
\end{aligned}\)

Multiplying with the monomial we get,

=4x²+8x-60

We have found the result of the expression 4(x−3)(x+5) that is, 4x2 + 8x − 60.

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 24 Exercise 3 Answer

Question: Find the Product Of The Expression 6(x+5)(x+4)?

Solution:

We have been given an expression 6(x+5)(x+4).

We have to multiply the given monomial with the given binomials.

We will find the result by multiplying the binomials first and then multiplying it with the monomial.

6(x+5)(x+4) multiplying the binomial we get,

⇒ \(\begin{aligned}
6(x+5)(x+4) & =6\left(x^2+5 x+4 x+20\right) \\
& =6\left(x^2+9 x+20\right)
\end{aligned}\)

Multiplying with the monomial we get, =6x²+54x+120

We have found the result of the expression 6(x+5)(x+4)​ that is, 6x2 + 54x + 120.

Page 24 Exercise 4 Answer

Question: Find the Product Of The Expression 2(x+3)(x−3)?

Solution:

We have been given an expression 2(x+3)(x−3).

We have to multiply the given monomial with the given binomials.

We will find the result by multiplying the binomials first and then multiplying it with the monomial.

The given expression is 2(x+3)(x-3)

multiplying the binomial we get,

⇒ \(\begin{aligned}
2(x+3)(x-3) & =2\left(x^2-3 x+3 x-9\right) \\
& =2\left(x^2-9\right)
\end{aligned}\)

Multiplying with the monomial we get,

=2x²-18

We have found the result of the expression 2(x+3)(x−3) that is, 2x2 − 18.

Page 24 Exercise 6 Answer

Question: Find the Product Of The Expression x(x−5)(x−4)?

Solution:

We have been given an expression x(x−5)(x−4).

We have to multiply the given monomial with the given binomials.

We will find the result by multiplying the binomials first and then multiplying it with the monomial.

The given expression is x(x-5)(x-4) multiplying the binomial we get,

x(x-5)(Xx4)=x(x²-4x-5x+20)

=x(x²-9x+20)

multiplying with the monomial we get,

=x³-9x²+20x

We have found the result of the expression x(x−5)(x−4) that is, x3 − 9x2 + 20x.

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 24 Exercise 3 Answer

Question: Find the Factors For The Trinomial 5x2 + 35x + 60?

Solution:

We have been given a trinomial 5x2 + 35x + 60.

We have to first factor out the biggest monomial we can. Then factor the trinomial that’s left into a binomial time a binomial.

We will find the result using the factorization method.

The given expression is, 5×3+35x+60′

Factoring out the monomial, we get

\(5 x^2+35 x+60=5\left(x^2+7 x+12\right)\)

Now, factoring out the binomial we get

⇒ \(\begin{aligned}
5\left(x^2+7 x+12\right) & =5\left(x^2+3 x+4 x+12\right) \\
& =5(x(x+3)+4(x+3)) \\
& =5(x+3)(x+4)
\end{aligned}\)

We have factorized the given trinomial 5x2 + 35x + 60 that is,5(x+3)(x+4).

Page 24 Exercise 4 Answer

Question: Find the Factors For The Trinomial x3 + 8x2 − 20x?

Solution:

We have been given a trinomial x3 + 8x2 − 20x.

We have to first factor out the biggest monomial we can. Then factor the trinomial that’s left into a binomial time a binomial.

We will find the result using the factorization method.

The given trinomial is x³+8x²-20x

Factoring out the monomial, we get

x³+8x²-20x=x(x²+8x-20)

Now, factoring out the binomial we get

⇒ \(\begin{aligned}
x\left(x^2+8 x-20\right) & =x\left(x^2+10 x-2 x-20\right) \\
& =x(x(x+10)-2(x+10)) \\
& =x(x+10)(x-2)
\end{aligned}\)

We have factorized the given trinomial x3 + 8x2 − 20x that is, x(x+10)(x−2).

Page 24 Exercise 6 Answer

Question: Find the Factors For The Trinomial a3 − 7a2 + 6a?

Solution:

We have been given a trinomial a3 − 7a2 + 6a.

We have to first factor out the biggest monomial we can. Then factor the trinomial that’s left into a binomial time a binomial.

We will find the result using the factorization method.

The given trinomial is a³-7a²+6a

Factoring out the monomial, we get

a³-7a²+6a=a(a²-7a+6)

⇒\(\begin{aligned}
a\left(a^2-7 a+6\right) & =a\left(a^2-a-6 a+6\right) \\
& =a(a(a-1)-6(a-1)) \\
& =a(a-1)(a-6)
\end{aligned}\)

We have factorized the given trinomial a3 − 7a2 + 6a that is, a(a−1)(a−6).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 25 Exercise 3 Answer

Question: Find the Product of the expression (6x+1)(2x+3)?

Solution:

We have been given an expression (6x+1)(2x+3).

We have to multiply the given pair of binomials.

We will find the result by multiplying each term of the first binomial must be multiplied by each term of the second binomial.

We have multiplied the given pair of binomials (6x+1)(2x+3) that is, 12x2 + 20x + 3.

The given pair of binomials is(6x+1)(2x+3) multiplying them we get,

⇒ \(\begin{aligned}
(6 x+1)(2 x+3) & =6 x \cdot 2 x+6 x .3+2 x \cdot 1+1.3 \\
& =12 x^2+18 x+2 x+3 \\
& =12 x^2+20 x+3
\end{aligned}\)

Page 25 Exercise 4 Answer

Question: Find the Product of the expression (5x+3)(3x+4)?

Solution:

We have been given an expression(5x+3)(3x+4).

We have to multiply the given pair of binomials.

We will find the result by multiplying each term of the first binomial must be multiplied by each term of the second binomial.

The given pair of binomials is(5x+3)(3x+4)
multiplying them we get,

⇒ \(\begin{aligned}
(5 x+3)(3 x+4) & =5 x .3 x+5 x .4+3.3 x+3.4 \\
& =15 x^2+20 x+9 x+12 \\
& =15 x^2+29 x+12
\end{aligned}\)

We have multiplied the given pair of binomials (5x+3)(3x+4) that is, 15x2 + 29x + 12.

Page 25 Exercise 6 Answer

Question: Find the Product of the expression (4x−1)(3x−1)?

Solution:

We have been given an expression(4x−1)(3x−1).

We have to multiply the given pair of binomials.

We will find the result by multiplying each term of the first binomial must be multiplied by each term of the second binomial.

The given pair of binomials is(4x-1)(3x-1)
multiplying them we get,

⇒ \(\begin{aligned}
(4 x-1)(3 x-1) & =4 x \cdot 3 x-1.4 x-1 \cdot 3 x+(-1) \cdot(-1) \\
& =12 x^2-4 x-3 x+1 \\
& =12 x^2-7 x+1
\end{aligned}\)

We have multiplied the given pair of binomials(4x−1)(3x−1) that is, 12x2 − 7x + 1.

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 25 Exercise 7 Answer

Question: Find the Product of the expression (3x−5)(2x−5)?

Solution:

We have been given an expression (3x−5)(2x−5).

We have to multiply the given pair of binomials.

We will find the result by multiplying each term of the first binomial must be multiplied by each term of the second binomial.

The given pair of binomials is(3x-5)(2x-5) multiplying them we get,

⇒ \(\begin{aligned}
(3 x-5)(2 x-5) & =3 x \cdot 2 x-5 \cdot 3 x-5 \cdot 2 x+(-5) \cdot(-5) \\
& =6 x^2-15 x-10 x+25 \\
& =6 x^2-25 x+25
\end{aligned}\)

We have multiplied the given pair of binomials (3x−5)(2x−5) that is, 6x2 − 25x + 25.

Page 25 Exercise 8 Answer

Question: Find the Product of the expression (4x−3)(x+3)?

Solution:

Given: – (4x−3)×(x+3)

To find – Product

⇒ \(\begin{aligned}
& \text { Given }-(4 x-3) \times(x+3) \\
& \text { we have }=(4 x-3) \times(x+3) \\
& \text { ie., } 4 x(x+3)+(-3) \times(x+3) \\
& \text { or } 4 x^2+12 x+(-3 x)-9 \\
& \text { or } 4 x^2+12 x-3 x-9 \\
& 4 x^2+9 x-9
\end{aligned}\)

Hence the product is 4x2 + 9x − 9.

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 25 Exercise 9 Answer

Question: Find the Product of the expression (3x+4) (3x−4)?

Solution:

Given – (3x+4) × (3x−4)

To find – Product

⇒ \(\begin{aligned}
& \text { Given }(3 x+4) \times(3 x-4) \\
& \text { we have }=(3 x+4) \times(3 x-4) \\
& =3 x(3 x+4)-4(3 x+4) \\
& =9 x^2+12 x-12 x-16 \\
& =9 x^2-16
\end{aligned}\)

Hence the product is 9x2 − 16.

Question: Find the Product of the expression (2x−3)(2x−3)?

Solution:

Page 25 Exercise 12 Answer

Given = (2x−3)×(2x−3)

To find = Product

⇒ \(\begin{aligned}
& \text { Given }=(2 x-3) \times(2 x-3) \\
& \text { we have }=(2 x-3) \times(2 x-3) \\
& =2 x(2 x-3)-3(2 x-3) \\
& =4 x^2-6 x-6 x+9 \\
& =4 x^2-12 x+9
\end{aligned}\)

Hence the product is 4x2 − 12x + 9

Question: Find the Product of the expression (4x+1)×(4x+1)?

Solution:

Page 25 Exercise 13 Answer

Given = (4x+1)×(4x+1)

To find =The Product

⇒ \(\begin{aligned}
& \text { Given }=(4 x+1) \times(4 x+1) \\
& \text { we have }=(4 x+1) \times(4 x+1) \\
& =4 x(4 x+1)+1(4 x+1) \\
& =16 x^2+4 x+4 x+1 \\
& =16 x^2+8 x+1
\end{aligned}\)

Hence the product is 16x2 + 8x + 1.

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 25 Exercise 14 Answer

Question: Expand the Polynomial (3x−7)2

Solution:

Given that (3x−7)2.

The aim is to find the expansion.

(3x-7)²

using the binomial theorem

⇒ \(\begin{aligned}
& (x+y)^n={ }^n C_0 x^n+{ }^n C_1 x^{n-1} y+\cdots+{ }^n C_n y^n, \\
& \text { Taking } x=3 x, y=-7, n=2, \\
& (3 x-7)^2={ }^2 C_0(3 x)^2+{ }^2 C_1(3 x)(-7)+{ }^2 C_2(-7)^2 \\
& (3 x-7)^2=9 x^2-42 x+49
\end{aligned}\)

The expansion is (3x−7)2 = 9x2 − 42x + 49.

Page 27 Exercise 1 Answer

Question: Find the factors of the Polynomial 3x2 + 4x + 1

Solution:

Given that 3x2 + 4x + 1.

The aim is to find the factor for 3x2 + 4x + 1.

Given that 3x2 + 4x + 1.

The expression can be written as,

⇒ \(\begin{aligned}
& 3 x^2+4 x+1=3 x^2+3 x+x+1 \\
& 3 x^2+4 x+1=3 x(x+1)+1(x+1) \\
& 3 x^2+4 x+1=(3 x+1)(x+1)
\end{aligned}\)

The factor for the expression is 3x2 + 4x + 1 = (3x+1)(x+1).

Page 27 Exercise 2 Answer

Question: Find the factors of the Polynomial 2x2 + 3x + 1

Solution:

Given that 2x2 + 3x + 1.

The aim is to find the factor for 2x2 + 3x + 1.

Given that 2x2 + 3x + 1.

the expression can be written as

⇒ \(\begin{aligned}
& 2 x^2+3 x+1=2 x^2+2 x+x+1 \\
& 2 x^2+3 x+1=2 x(x+1)+1(x+1) \\
& 2 x^2+3 x+1=(2 x+1)(x+1)
\end{aligned}\)

The factored expression is, 2x2 + 3x + 1 = (2x+1)(x+1).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 27 Exercise 4 Answer

Question: Find the factors of the Polynomial 4x2 + 5x + 1

Solution:

Given that 4x2 + 5x + 1.

The aim is to find the factor for 4x2 + 5x + 1.

Given that 4x²+5x+1 the expression can be written as

⇒ \(\begin{aligned}
& 4 x^2+5 x+1=4 x^2+4 x+x+1 \\
& 4 x^2+5 x+1=4 x(x+1)+1(x+1) \\
& 4 x^2+5 x+1=(4 x+1)(x+1)
\end{aligned}\)

The expression is, 4x2 + 5x + 1 = (4x+1)(x+1).

Question: Find the factors of the Polynomial 2x2 − 3x + 1

Solution:

Page 27 Exercise 6 Answer

Given that 2x2 − 3x + 1.

The aim is to find the factor for 2x2 − 3x + 1.

Given that 2x2 − 3x + 1. the expression can be written as

⇒ \(\begin{aligned}
& 2 x^2-3 x+1=2 x^2-2 x-x+1 \\
& 2 x^2-3 x+1=2 x(x-1)-1(x-1) \\
& 2 x^2-3 x+1=(2 x-1)(x-1)
\end{aligned}\)

The factor for the expression is (2x−1)(x−1).

Page 27 Exercise 7 Answer

Question: Find the factors of the Polynomial 3x2 − 2x − 1

Solution:

Given that 3x2 − 2x − 1.

The aim is to find the factors for the 3x2 − 2x − 1.

Given that 2x2 − 3x + 1. the expression can be written as

⇒ \(\begin{aligned}
& 3 x^2-2 x-1=3 x^2-3 x+x-1 \\
& 3 x^2-2 x-1=3 x(x-1)+(x-1) \\
& 3 x^2-2 x-1=(3 x+1)(x-1)
\end{aligned}\)

The factor for the expression is 3x2 − 2x − 1 = (3x+1)(x−1).

Key To Algebra Book 4 Chapter 8 Part 2 Polynomial Problems

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 27 Exercise 8 Answer

Question: Find the factors of the Polynomial 3x2 + 2x − 1

Solution:

Given that 3x2 + 2x − 1.

The aim is to find the factor for the trinomial.

Given that 3x2 + 2x − 1.

The expression can be written as

⇒ \(\begin{aligned}
& 3 x^2+2 x-1=3 x^2+3 x-x-1 \\
& 3 x^2+2 x-1=3 x(x+1)-1(x+1) \\
& 3 x^2+2 x-1=(3 x-1)(x+1)
\end{aligned}\)

The factor for the trinomial is 3x2 + 2x − 1 = (3x−1)(x+1).

Page 27 Exercise 12 Answer

Question: Find the factors of the Polynomial 2x2 − 7x + 3

Solution:

Given that 2x2 − 7x + 3.

The aim is to find the factor for the given expression.

Given that 2x2 − 7x + 3.

The expression can be written as

⇒ \(\begin{aligned}
& 2 x^2-7 x+3=2 x^2-6 x-x+3 \\
& 2 x^2-7 x+3=2 x(x-3)-1(x-3) \\
& 2 x^2-7 x+3=(2 x-1)(x-3)
\end{aligned}\)

The factor for the given expression is (2x−1)(x−3).

 

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 27 Exercise 13 Answer

Question: Find the factors of the Polynomial 2x2 − 5x − 3

Solution:

Given that 2x2 − 5x − 3.

The aim is to find the factor for the given expression.

Given that 2x2 − 5x − 3.

The expression can be written as

\(\begin{aligned}
& 2 x^2-5 x-3=2 x^2-6 x+x-3 \\
& 2 x^2-5 x-3=2 x(x-3)+1(x-3) \\
& 2 x^2-5 x-3=(2 x+1)(x-3)
\end{aligned}\)

The factor for the expression is 2x2 − 5x − 3 = (2x+1)(x+3).

Page 27 Exercise 14 Answer

Question: Find the factors of the Polynomial 2x2 + 5x − 3

Solution:

Given that 2x2 + 5x − 3.

The aim is to find the factor for the 2x2 + 5x − 3.

Given that 2x2 + 5x − 3.

The expression can be written as,

⇒ \(\begin{aligned}
& 2 x^2+5 x-3=2 x^2+6 x-x-3 \\
& 2 x^2+5 x-3=2 x(x+3)-1(x+3) \\
& 2 x^2+5 x-3=(2 x-1)(x+3)
\end{aligned}\)

The factor for the expression is 2x2 + 5x − 3 = (2x−1)(x+3).

Page 27 Exercise 15 Answer

Question: Find the factors of the trinomial 2x2 − x − 3

Solution:

Given that 2x2 − x − 3.

The aim is to find the expression for the 2x2 − x − 3.

Given that 2x2 − x − 3.
The expression can be written as

⇒ \(\begin{aligned}
& 2 x^2+5 x-3=2 x^2+6 x-x-3 \\
& 2 x^2+5 x-3=2 x(x+3)-1(x+3) \\
& 2 x^2+5 x-3=(2 x-1)(x+3)
\end{aligned}\)

The factor for the trinomial is 2x2 − x − 3 = (x+1)(2x−3).

 

Page 27 Exercise 17 Answer

Question: Find the factors of the trinomial 4a2 + 3a − 1

Solution:

To factorize the given trinomials 4a2 + 3a − 1

Given trinomials 4a²+3a-1

From this trinomial, we see that a=4,b=3,c=1

Now we have to find two factors whose product is 4x-1=-4 and the sum is 3 we get, 4and-1 as two factors since their product is-4 and the sum is 3 hence

⇒ \(\begin{aligned}
4 a^2+3 a-1 & =4 a^2+4 a-a-1 \\
& =4 a(a+1)-1(a+1) \\
& =(4 a-1)(a+1)
\end{aligned}\)

Therefore the factors of the trinomial of 4a2 + 3a − 1 = (4a−1)(a+1).

Page 28 Exercise 4 Answer

Question: Find the factors of the trinomial 4x2 − 11x + 6

Solution:

Given trinomial: 4x2 − 11x + 6

It is asked to find the factors of the given trinomial.

Given trinomial: 4×2-11x+6

Factoring the given trinomial

4x²-11x+6

⇒ \(\begin{aligned}
& \Rightarrow 4 x^2-(8+3) x+6 \\
& \Rightarrow 4 x^2-8 x-3 x+6 \\
& \Rightarrow 4 x(x-2)-3(x-2) \\
& \Rightarrow(4 x-3)(x-2)
\end{aligned}\)

Checking by multiplying the binomials

(x-2)(4x-3)
⇒ 4x²-3x-8x+6
⇒4x²-11x+6

Therefore, the factors of trinomial 4x2 − 11x + 6 = (x−2)(4x−3).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 28 Exercise 5 Answer

Question: Find the factors of the trinomial 16x2 − 2x − 5

Solution:

Given trinomial: 16x2 − 2x − 5

It is asked to find the factors of the given trinomial.

16x2 − 2x − 5

Factoring the given trinomial: 16x2 − 2x − 5

⇒ \(\begin{aligned}
& \Rightarrow 16 x^2-(10-8) x-5 \\
& \Rightarrow 16 x^2-10 x+8 x-5 \\
& \Rightarrow 2 x(8 x-5)+1(8 x-5) \\
& \Rightarrow(8 x-5)(2 x+1)
\end{aligned}\)

Checking by multiplying the binomials

⇒ \(\begin{aligned}
& (8 x-5)(2 x+1) \\
& \Rightarrow 16 x^2+8 x-10 x-5 \\
& \Rightarrow 16 x^2-2 x-5
\end{aligned}\)

Therefore, the factors of trinomial 16x2 − 2x − 5 = (8x−5)(2x+1).

Page 28 Exercise 6 Answer

Question: Find the factors of the trinomial 6x2 + 17x + 5

Solution:

Given trinomial: 6x2 + 17x + 5

It is asked to find the factors of the given trinomial.

Given trinomial: 6x2 + 17x + 5
Factoring the given trinomial: 6x2 + 17x + 5

⇒ \(\begin{aligned}
& \Rightarrow 6 x^2+(15+2) x+5 \\
& \Rightarrow 6 x^2+15 x+2 x+5 \\
& \Rightarrow 3 x(2 x+5)+1(2 x+5) \\
& \Rightarrow(3 x+1)(2 x+5)
\end{aligned}\)

Checking by multiplying the binomials

⇒ \(\begin{aligned}
& (3 x+1)(2 x+5) \\
& \Rightarrow 6 x^2+15 x+2 x+5 \\
& \Rightarrow 6 x^2+17 x+5
\end{aligned}\)

Therefore, the factors of trinomial 6x2 + 17x + 5 = (2x+5)(3x+1).

Page 28 Exercise 7 Answer

Question: Find the factors of the trinomial 6x2 + 13x + 5

Solution:

Given trinomial: 6x2 + 13x + 5

It is asked to find the factors of the given trinomial.

Given trinomial: 6x2 + 13x + 5
Factoring the given trinomial: 6x2 + 13x + 5

\(\begin{aligned}
& 6 x^2+13 x+5 \\
\Rightarrow & 6 x^2+(10+3) x+5 \\
\Rightarrow & 6 x^2+10 x+3 x+5 \\
\Rightarrow & 2 x(3 x+5)+(3 x+5) \\
\Rightarrow & (2 x+1)(3 x+5)
\end{aligned}\)

⇒ \(\begin{aligned}
& (2 x+1)(3 x+5) \\
\Rightarrow & 6 x^2+10 x+3 x+5 \\
\Rightarrow & 6 x^2+13 x+5
\end{aligned}\)

Therefore, the factors of trinomial 6x2 + 13x + 5 = (3x+5)(2x+1).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 28 Exercise 8 Answer

Question: Find the factors of the trinomial 6x2 − 13x − 5

Solution:

Given trinomial: 6x2 − 13x − 5

It is asked to find the factors of the given trinomial.

Given trinomial: 6x2 − 13x − 5

Factoring the given trinomial: 6x2 − 13x − 5

⇒ \(\begin{aligned}
& \Rightarrow 6 x^2-(15-2) x-5 \\
& \Rightarrow 6 x^2-15 x+2 x-5 \\
& \Rightarrow 3 x(2 x-5)+1(2 x-5) \\
& \Rightarrow(3 x+1)(2 x-5)
\end{aligned}\)

Checking by multiplying the binomial:

⇒ \(\begin{aligned}
& (3 x+1)(2 x-5) \\
& \Rightarrow 6 x^2-15 x+2 x-5 \\
& \Rightarrow 6 x^2-13 x-5
\end{aligned}\)

Therefore, the factors of trinomial 6x2 − 13x − 5 = (2x−5)(3x+1).

Page 28 Exercise 9 Answer

Question: Find the factors of the trinomial 6x2 − 13x + 5

Solution:

Given trinomial: 6x2 − 13x + 5

It is asked to find the factors of the given trinomial.

Given trinomial: 6x2 − 13x + 5

Factoring the given trinomial: 6x2 − 13x + 5

⇒ \(\begin{aligned}
& 6 x^2-13 x+5 \\
\Rightarrow & 6 x^2-(10+3) x+5 \\
\Rightarrow & 6 x^2-10 x-3 x+5 \\
\Rightarrow & 2 x(3 x-5)-(3 x-5) \\
\Rightarrow & (2 x-1)(3 x-5)
\end{aligned}\)

Checking by multiplying the binomial

⇒ \(\begin{aligned}
& (3 x-5)(2 x-1) \\
& \Rightarrow 6 x^2-3 x-10 x+5 \\
& \Rightarrow 6 x^2-13 x+5
\end{aligned}\)

Therefore, the factors of trinomial 6x2 − 13x + 5 = (3x−5)(2x−1).

Page 28 Exercise 10 Answer

Question: Find the factors of the trinomial 6x2 − 7x − 5

Solution:

Given trinomial: 6x2 − 7x − 5

It is asked to find the factors of the given trinomial.

Given trinomial: 6x2 − 7x − 5

Factoring the given trinomial:

⇒ \(\begin{aligned}
& 6 x^2-7 x-5 \\
\Rightarrow & 6 x^2-(10-3) x-5 \\
\Rightarrow & 6 x^2-10 x+3 x-5 \\
\Rightarrow & 6 x^2-10 x+3 x-5 \\
\Rightarrow & 2 x(3 x-5)+(3 x-5) \\
\Rightarrow & (2 x+1)(3 x-5)
\end{aligned}\)

Checking by multiplying the binomials

\(\begin{aligned}
& (2 x+1)(3 x-5) \\
\Rightarrow & 6 x^2-10 x+3 x-5 \\
\Rightarrow & 6 x^2-7 x-5
\end{aligned}\)

Therefore, the factors of trinomial 6x2 − 7x − 5 = (3x−5)(2x+1).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 28 Exercise 11 Answer

Question: Find the factors of the trinomial 6x2 + 7x − 5

Solution:

Given trinomial: 6x2 + 7x − 5

It is asked to find the factors of the given trinomial.

Given trinomial: 6x2 + 7x − 5

Factoring the given trinomial:

⇒ \(\begin{aligned}
& 6 x^2+7 x-5 \\
\Rightarrow & 6 x^2+(10-3) x-5 \\
\Rightarrow & 6 x^2+10 x-3 x-5 \\
\Rightarrow & 2 x(3 x+5)-(3 x+5) \\
\Rightarrow & (2 x-1)(3 x+5)
\end{aligned}\)

Checking by multiplying the binomials

⇒ \(\begin{aligned}
& (3 x+5)(2 x-1) \\
\Rightarrow & 6 x^2-3 x+10 x-5 \\
\Rightarrow & 6 x^2+7 x-5
\end{aligned}\)

Therefore, the factors of trinomial 6x2 + 7x − 5 = (3x+5)(2x−1).

Page 28 Exercise 12 Answer

Question: Find the factors of the trinomial 8x2 + 14x + 3

Solution:

Given trinomial: 8x2 + 14x + 3

It is asked to find the factors of the given trinomial.

Given trinomial: 8x2 + 14x + 3

Factoring the given trinomial:

⇒ \(\begin{aligned}
& 8 x^2+14 x+3 \\
\Rightarrow & 8 x^2+(12+2) x+3 \\
\Rightarrow & 8 x^2+12 x+2 x+3 \\
\Rightarrow & 4 x(2 x+3)+1(2 x+3) \\
\Rightarrow & (2 x+3)(4 x+1)
\end{aligned}\)

Checking by multiplying the binomial

⇒ \(\begin{aligned}
& (2 x+3)(4 x+1) \\
\Rightarrow & 8 x^2+2 x+12 x+3 \\
\Rightarrow & 8 x^2+14 x+3
\end{aligned}\)

Therefore, the factors of trinomial 8x2 + 14x + 3 = (2x+3)(4x+1).

 

Page 28 Exercise 13 Answer

Question: Find the factors of the trinomial 8x2 − 10x + 3

Solution:

Given trinomial: 8x2 − 10x + 3

It is asked to find the factors of the given trinomial.

Given trinomial: 8x2 − 10x + 3

Factoring the given trinomial:

⇒ \(\begin{aligned}
& 8 x^2-10 x+3 \\
\Rightarrow & 8 x^2-(6+4)+3 \\
\Rightarrow & 8 x^2-6 x-4 x+3 \\
\Rightarrow & 2 x(4 x-3)-1(4 x-3) \\
\Rightarrow & (4 x-3)(2 x-1)
\end{aligned}\)

Checking by multiplying the binomials:

⇒ \(\begin{aligned}
& (4 x-3)(2 x-1) \\
\Rightarrow & 8 x^2-4 x-6 x+3 \\
\Rightarrow & 8 x^2-10 x+3
\end{aligned}\)

Therefore, the factors of trinomial 8x2 − 10x + 3 = (4x−3)(2x−1).

Solutions For Multiplying And Factoring Polynomials Part 2 Chapter 8 Key To Algebra Book 4

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 28 Exercise 14 Answer

Question: Find the factors of the trinomial 8x2 + 25x + 3

Solution:

Given trinomial: 8x2 + 25x + 3

It is asked to find the factors of the given trinomial.

Given trinomial: 8x2 + 25x + 3

Factoring the given trinomial:

⇒ \(\begin{aligned}
& 8 x^2+25 x+3 \\
\Rightarrow & 8 x^2+(24+1) x+3 \\
\Rightarrow & 8 x^2+24 x+x+3 \\
\Rightarrow & 8 x^2+24 x+x+3 \\
\Rightarrow & 8 x(x+3)+1(x+3) \\
\Rightarrow & (8 x+1)(x+3)
\end{aligned}\)

Checking By  multiplying the binomials:

⇒ \(\begin{aligned}
& (x+3)(8 x+1) \\
\Rightarrow & 8 x^2+x+24 x+3 \\
\Rightarrow & 8 x^2+25 x+3
\end{aligned}\)

Therefore, the factors of trinomial 8x2 + 25x + 3 = (x+3)(8x+1).

 

Page 28 Exercise 15 Answer

Question: Find the factors of the trinomial 6x2 + 14x + 4

Solution:

Given trinomial: 6x2 + 14x + 4

It is asked to find the factors of the given trinomial.

Given trinomial: 6x2 + 14x + 4

Factoring the given trinomial:

⇒ \(\begin{aligned}
& 6 x^2+14 x+4 \\
\Rightarrow & 6 x^2+(12+2) x+4 \\
\Rightarrow & 6 x^2+12 x+2 x+4 \\
\Rightarrow & 6 x(x+2)+2(x+2) \\
\Rightarrow & (6 x+2)(x+2)
\end{aligned}\)

Checking By  multiplying the binomials:

⇒ \(\begin{aligned}
& (x+2)(6 x+2) \\
\Rightarrow & 6 x^2+2 x+12 x+4 \\
\Rightarrow & 6 x^2+14 x+4
\end{aligned}\)

Therefore, the factors of trinomial 6x2 + 14x + 4 = (2x+4)(3x+1).

 

Page 28 Exercise 16 Answer

Question: Find the factors of the trinomial 6x2 − 10x + 4

Solution:

Given trinomial: 6x2 − 10x + 4

It is asked to find the factors of the given trinomial.

Given trinomial: 6x2 − 10x + 4
Factoring the given trinomial:

⇒ \(\begin{aligned}
& 6 x^2-10 x+4 \\
\Rightarrow & 6 x^2-(6+4) x+4 \\
\Rightarrow & 6 x^2-6 x-4 x+4 \\
\Rightarrow & 6 x(x-1)-4(x-1) \\
\Rightarrow & (x-1)(6 x-4)
\end{aligned}\)

Checking By  multiplying the binomials:

⇒ \(\begin{aligned}
& (x-1)(6 x-4) \\
\Rightarrow & 6 x^2-4 x-6 x+4 \\
\Rightarrow & 6 x^2-10 x+4
\end{aligned}\)

Therefore, the factors of trinomial(x−1)(6x+4) = 6x2 − 10x + 4.

 

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 28 Exercise 17 Answer

Question: Find the factors of the trinomial 6x2 + 25x + 4

Solution:

Given trinomial: 6x2 + 25x + 4

It is asked to find the factors of the given trinomial.

Given trinomial: 6x2 + 25x + 4
Factoring the given trinomial:

⇒ \(\begin{aligned}
& 6 x^2+25 x+4 \\
\Rightarrow & 6 x^2+(24+1) x+4 \\
\Rightarrow & 6 x^2+24 x+x+4 \\
\Rightarrow & 6 x(x+4)+1(x+4) \\
\Rightarrow & (x+4)(6 x+1)
\end{aligned}\)

Checking By  multiplying the binomials:

⇒ \(\begin{aligned}
& (x+4)(6 x+1) \\
\Rightarrow & 6 x^2+x+24 x+4 \\
\Rightarrow & 6 x^2+25 x+4
\end{aligned}\)

Therefore, the factors of trinomial 6x2 + 25x + 4 = (x+4)(6x+1).

Page 28 Exercise 18 Answer

Question: Find the factors of the trinomial 6x2 − 23x − 4

Solution:

Given trinomial: 6x2 − 23x − 4

It is asked to find the factors of the given trinomial.

Given trinomial: 6x2 − 23x − 4

Factoring the given trinomial:

⇒ \(\begin{aligned}
& 6 x^2-2 x-4 \\
\Rightarrow & 6 x^2-(6-4) x-4 \\
\Rightarrow & 6 x^2-6 x+4 x-4 \\
\Rightarrow & 6 x(x-1)+4(x-1) \\
\Rightarrow & (x-1)(6 x+4)
\end{aligned}\)

Checking by multiplying the binomials:

⇒ \(\begin{aligned}
& (x-1)(6 x+4) \\
\Rightarrow & 6 x^2+4 x-6 x-4 \\
\Rightarrow & 6 x^2-2 x-4
\end{aligned}\)

Therefore, the factors of trinomial 6x2 − 23x − 4 = (x−4)(6x+1).

Question: Find the factors of the trinomial 6x2 − 2x − 4

Solution:

Page 28 Exercise 19 Answer

Given trinomial: 6x2 − 2x − 4

It is asked to find the factors of the given trinomial.

Given trinomial: 6x2 − 2x − 4

Factoring the given trinomial:

⇒ \(\begin{aligned}
& 6 x^2-2 x-4 \\
\Rightarrow & 6 x^2-(6-4) x-4 \\
\Rightarrow & 6 x^2-6 x+4 x-4 \\
\Rightarrow & 6 x(x-1)+4(x-1) \\
\Rightarrow & (x-1)(6 x+4)
\end{aligned}\)

Checking by multiplying the binomials:

⇒ \(\begin{aligned}
& (x-1)(6 x+4) \\
\Rightarrow & 6 x^2+4 x-6 x-4 \\
\Rightarrow & 6 x^2-2 x-4
\end{aligned}\)

Therefore, the factors of tr

Therefore, the factors of trinomial 6x2 − 2x − 4 = (x−1)(6x+4).

Page 28 Exercise 20 Answer

Question: Find the factors of the trinomial 6x2 + 10x − 4

Solution:

Given trinomial: 6x2 + 10x − 4

It is asked to find the factors of the given trinomial

Given trinomial: 6x2 + 10x − 4
Factoring the given trinomial:

⇒ \(\begin{aligned}
& 6 x^2+10 x-4 \\
\Rightarrow & 6 x^2+(12-2) x-4 \\
\Rightarrow & 6 x^2+12 x-2 x-4 \\
\Rightarrow & 6 x(x+2)-2(x+2) \\
\Rightarrow & (x+2)(6 x-2)
\end{aligned}\)

Checking by multiplying the binomials:

⇒ \(\begin{aligned}
& (x+2)(6 x-2) \\
\Rightarrow & 6 x^2-2 x+19 x-4 \\
\Rightarrow & 6 x^2+10 x-4
\end{aligned}\)

Therefore, the factors of trinomial 6x2 + 10x − 4 = (x+2)(6x−2).

Page 28 Exercise 21 Answer

Question: Find the factors of the trinomial 6x2 + 5x − 4

Solution:

Given trinomial: 6x2 + 5x − 4

It is asked to find the factors of the given trinomial.

Given trinomial: 6x2 + 5x − 4
Factoring the given trinomial:

⇒ \(\begin{aligned}
& 6 x^2+5 x-4 \\
\Rightarrow & 6 x^2+(8-3) x-4 \\
\Rightarrow & 6 x^2+8 x-3 x-4 \\
\Rightarrow & 2 x(3 x+4)-1(3 x+4) \\
\Rightarrow & (3 x+4)(2 x-1)
\end{aligned}\)

Checking by multiplying the binomials:

⇒ \(\begin{aligned}
& (3 x+4)(2 x-1) \\
\Rightarrow & 6 x^2-3 x+8 x-4 \\
\Rightarrow & 6 x^2+5 x-4
\end{aligned}\)

Therefore, the factors of trinomial 6x2 + 5x − 4 = (3x+4)(2x−1).

 

Page 28 Exercise 24 Answer

Question: Find the factors of the trinomial 16x2 − 38x − 5

Solution:

Given the trinomial 16x2 − 38x − 5

Here it is asked to factor the trinomial.

Given the trinomial: 16x²-38-5

we can break the expression

16x²-38-5=(16x²+2x)+(-40x-5)

here the first term can be written as

16x²+2x=2x(8x+1)

The second term can be written as

-40x-5=-5(8x+1)

so we can write that

⇒ \(\begin{aligned}
16 x^2-38 x-5 & =\left(16 x^2+2 x\right)+(-40 x-5) \\
& =2 x(8 x+1)-5(8 x+1) \\
& =(8 x+1)(2 x-5)
\end{aligned}\)

Therefore, the required answer is (8x+1)(2x−5).

Page 28 Exercise 26 Answer

Question: Find the factors of the Polynomial 16x2 + 79x − 5

Solution:

Given the trinomial 16x2 + 79x − 5

Here it is asked to factor the trinomial.

Given the trinomial: 16x2 + 79x − 5

we can break the expression

16x2 + 79x − 5=(16x²+2x)+(80x-5)

here the first term can be written as

16x²+2x=2x(16x+1)

The second term can be written as

80x-5=-5(16x-1)

so we can write that

⇒ \(\begin{aligned}
16 x^2+79 x-5 & =\left(16 x^2-x\right)+(80 x-5) \\
& =x(16 x-1)+5(16 x-1) \\
& =(16 x-1)(x+5)
\end{aligned}\)

Verification \(\begin{aligned}
& (16 x-1)(x+5) \\
= & 16 x^2+80 x-x-5 \\
= & 16 x^2+79 x-5
\end{aligned}\)

Since the product of factors is equal to the factorized trinomial, hence we can say that the obtained factors are correct.

Therefore, the required answer is (16x−1)(x+5). On determining the product of these factors we obtained the trinomial 16x2 + 79x − 5. Hence, the answer is verified.

Page 28 Exercise 28 Answer

Question: Find the factors of the Polynomial 16x2 + 11x − 5

Solution:

Given the trinomial 16x2 + 11x − 5

Here it is asked to factor the trinomial.

Given the trinomial: 16x2 + 11x − 5

we can break the expression

16x2 + 11x − 5=(16x²+5x)+(16x-5)

here the first term can be written as

16x²-5x=2x(16x+1)

The second term can be written as

16x-5=1(16x-5)

so we can write that

⇒ \(\begin{aligned}
16 x^2+11 x-5 & =\left(16 x^2-5 x\right)+(16 x-5) \\
& =x(16 x-5)+1(16 x-5) \\
& =(16 x-5)(x+1)
\end{aligned}\)

Therefore, the required answer is (16x−5)(x+1).

Page 29 Exercise 1 Answer

Question: Find The Product Of The expression (2s-3)(2s+3)

Solution:

Given the expression

(2s-3)(2s+3)

Here it is asked to multiply the expression.

Given the expression

we know that (a+b)(a-b)=a²-b²

Here we can multiply

(2s-3)(2s+3)=(2s)²-(3)² =4s²-9

Therefore, the answer is 9x2 − 4.

Mcgraw Hill Key To Algebra Chapter 8 Part 2 Problem Walkthrough

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 29 Exercise 3 Answer

Question: Find the Product (2s−3)(2s+3)?

Solution:

Given the expression

(2s−3)(2s+3)

Here it is asked to multiply the expression.

Given the expression

(8x-4)(8x+4)

we know that (a+b)(a-b)=a²-b²

Here we can multiply

(8x-4)(8x+4)=(8x)²-4²
=64x²-16

Therefore, the answer is 4s2 − 9.

Page 29 Exercise 4 Answer

Question: Find the Product (8x−4)(8x+4)?

Solution:

Given the expression

(8x−4)(8x+4)

Here it is asked to multiply the expression.

Given the expression

(8x-4)(8x+4)

we know that

(a+b)(a-b)=a²-b²

here we can multiply

(8x-4)(8x+4)=(8x)²-4² =64x²-16

Therefore, the answer is 64x2 − 16.

Page 29 Exercise 1 Answer

Question: Find the Product (2x+3y)(x−2y)?

Solution:

Given the expression

(2x+3y)(x−2y)

Here it is asked to multiply the expression.

Given the expression

(2x+3y)(x-2y)

we know that

(a+b)(x+d)=ab+ad+bc+bd

here we can multiply

\(\begin{aligned}
(2 x+3 y)(x-2 y) & =2 x x+2 x(-2 y)+3 y x+3 y(-2 y) \\
& =2 x^2-4 x y+3 x y-6 y^2 \\
& =2 x^2-x y-6 y^2
\end{aligned}\)

Therefore, the answer is 2x2 − xy − 6y2.

Page 29 Exercise 2 Answer

Question: Find the Product (5x+y)(3x+2y)?

Solution:

Given:

(5x+y)(3x+2y)

To find:

The multiplication

Apply (a+b)(c+d) = ac + ad + bc + bd

Given:

(5x+y)(3x+y)
we known that

(a+b )(c+d)=ax+ad+bc+bd

here we can apply

⇒ \(\begin{aligned}
(5 x+y)(3 x+2 y) & =5 x \cdot 3 x+5 x \cdot 2 y+y \cdot 3 x+y \cdot 2 y \\
& =15 x^2+10 x y+3 x y+2 y^2 \\
& =15 x^2+13 x y+2 y^2
\end{aligned}\)

The multiplication: (5x+y)(3x+2y) = 15x2 + 13xy + 2y2

Page 29 Exercise 4 Answer

Question: Find the Product (2x+5y)(2x−5y)?

Solution:

Given:

(2x+5y)(2x−5y)

To find:

The multiplication

Apply (a+b)(c+d) = ac + ad + bc + bd

Given:

(2x+5y)(2x-5y)

we know that

(a+b)(a-b)=a²-b²

Here we can multiply

(2x+5y)(2x-5y)=(2x)²-(5y)² =4x²-25y²

The multiplication: (2x+5y)(2x−5y) = 4x2 − 25y2

Page 29 Exercise 1 Answer

Question: Find the factors of the Equation 16x2 − 9?

Solution:

Given:

16x2 − 9

To find:

The factors

Apply the difference of squares formula

Given 16x2 − 9

To find the factors of the expression:

⇒ \(\begin{aligned}
& 16 x^2-9=4^2 x^2-3^2 \\
& 16 x^2-9=(4 x)^2-3^2 \\
& 16 x^2-9=(4 x+3)(4 x-3)
\end{aligned}\)

∴ x²-y²=(x+y)(x-y)

The factors of the expression: 16x2 − 9 = (4x+3)(4x−3)

Page 29 Exercise 3 Answer

Question: Find the factors of the Equation 36x2 − 100?

Solution:

Given:

36x2 − 100

To find:

The factors

Apply the difference of squares formula

Given expression 36x2 − 100

To find the factors of the expression:

\(\begin{aligned}
& 36 x^2-100=4.9 x^2-4.25 \\
& 36 x^2-100=4\left(9 x^2-25\right) \\
& 36 x^2-100=4\left((3 x)^2-5^2\right) \\
& 36 x^2-100=4(3 x+5)(3 x-5)
\end{aligned}\)

∴ x²-y²=(x+y)(x-y)

The factors: 36x2 − 100 = 4(3x+5)(3x−5)

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 2 Page 29 Exercise 4 Answer

Question: Find the factors of the Equation 81y2 − 1?

Solution:

Given:

81y2 − 1

To find:

The factors

Apply the difference of squares formula

81y²-1

To find the factors of the expression:

⇒ \(\begin{aligned}
& 81 y^2-1=9^2 y^2-1 \\
& 81 y^2-1=(9 y)^2-1^2 \\
& 81 y^2-1=(9 y+1)(9 y-1)
\end{aligned}\)

∴ x²-y²=(x+y)(x-y)

The factors: 81y2 − 1 = (9y+1)(9y−1)

Page 29 Exercise 1 Answer

Question: Find the factors of the Equation 2x2 + 5xy + 3y2?

Solution:

Given:

2x2 + 5xy + 3y2

To find:

Given: 2x2 + 5xy + 3y2

Group into (ax²+4xy)+(vxy+cy²)

To find the factors of the expression:

2x2+5xy+3y2=(2x2+2xy)+(-3xy-3y2)

∴ 4=2,v=3

Factor out common term 3a-2b

2x2+5xy+3y2=2x (x+y)+3y(x+y)

Factor out common term x+y

2x2+5xy+3y2=2x (x+y)+3y(2x+3y)

The factors: 2x2 + 5xy + 3y2 = (x+y)(2x+3y)

Page 29 Exercise 3 Answer

Question: Find the factors of the Equation 9a2 − 3ab − 2b2?

Solution:

Given:

9a2 − 3ab − 2b2

To find:

The factors

Group​into​ (ax2+uxy) + (vxy+cy2)

Take common things out

Given: 9a²-3ab-2b²

Group into (ax²+4xy)+(vxy+(y²)

To find the factors of the expression:

9a2-3ab-2b2=(9a2+3ab)+(-6ab-2b2)

∴ 4=3,v=-6

Factor out common term 3a-2b

9a2-3ab -2b2=3a(3a+b)-2b(3a+b)

Factor out common term 3a+b

9a2-3ab -2b2=3a(3a+b)(3a-2b)

The factors: 9a2 − 3ab − 2b2 = (3a+b)(3a−2b)

Page 29 Exercise 4 Answer

Question: Find the factors of the polynomial 9x2 − 16y2?

Solution:

Given:

9x2 − 16y2

To find: The factors

Apply the difference of squares formula

9x2 − 16y2

To find the factors of the expressions:

⇒ \(\begin{aligned}
& 9 x^2-16 y^2=3^2 x^2-4^2 y^2 \\
& 9 x^2-16 y^2=(3 x)^2-(4 y)^2 \\
& 9 x^2-16 y^2=(3 x+4 y)(3 x-4 y)
\end{aligned}\)

∴ x2-y2=(x+y)(x-y)

The factors: 9x2 − 16y2 = (3x+4y)(3x−4y)

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 1

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials

Page 16 Exercise 1 Answer

Question: Find The Product of the Expressions (x+3)(x+2)

Solution:

Given the product expression: (x+3)(x+2)

To multiply out the two binomials x+3 and x+2 and write its product.

Now we multiply out each term of one polynomial to another polynomial:

(x+3)(x+2)

(x+3)(x+2)=x(x+2)+3(x+2)

(using the distributive property)

=x²+5x+3.2

(since x1.x²=x1+1 and combining like terms of the power of x

=x2+5x+6

The product we can write:

3.2=3+3

=6

The final multiplied expression is: (x+3)(x+2) = x2 + 5x + 6

Question: Find The Product of the Expressions (y+4)(y+10)

Solution:

Given the product expression: (y+4)(y+10)

Multiply the binomials (y+4) and (y+10) and write its product.

Now we multiply out each term of one polynomial to another polynomial:

(x+3(x+2)

(x+3)(x+2)= x

The final multiplied expression is: (y+4)(y+10) = y2 + 14y + 40

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 1

Question: Find The Product of the Expressions (x+5)(x+6)

Solution:

Given expression: (x+5)(x+6)

Multiply the binomials (x+5) and (x+6) and write the product.

Now we multiply out each term of one polynomial to another polynomial:

(x+5)(x+6)=x(x+6)+5(x+6)

=x.x+6x+5x+5.6 (using distributive law)

=x2+11x+5.6

(since x1.x1=x1+1 and combining like terms of x

The= x2+11x+30

The product can be viewed as

5.6=6+6+6+6+6
=12+12+6
=30

The final multiplied expression is: (x+5)(x+6) = x2 + 11x + 30

Mcgraw Hill Key To Algebra Book 4 Chapter 8 Solutions

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 1 Page 16 Exercise 6 Answer

Question: Find The Product of the Expressions (x+1)(x+6)

Solution:

Given the product expression: (x+1)(x+6)

To multiply the binomials (x+5) and (x+6) and write its product.

Now we multiply out each term of one polynomial to another polynomial:

Given the product expression: (y+4)(y+10)
(y+4)(y+10)=y(y+10)4(y+10)
=y.y+10y+4y+4.10
(using distributive law)

=y2+14y+4.10

(since x1.x1= x1+1 and combining like terms of power of x

=y2+14y+4.10

(since x1.x1=x1+1 and combining like terms of power of x)

=y2+14y +40

The product can be viewed as:

4.10=10+10+10+10
=20+20
=40

The final multiplied expression is: (x+1)(x+6) = x2 + 7x + 6

Page 16 Exercise 7 Answer

Question: Find The Product of the Expressions (a+8)(a+9)

Solution:

Given product expression: (a+8)(a+9)

Multiply the binomials (a+8) and (a+9) and write its product.

Now we multiply out each term of one polynomial to another polynomial:

Given the product expression:(x+5)(x+6)

(x+5)(x+6)=x(x+6)+5(x+6)

=x.x+6x+5x+5.6 (using distributive law)

=x2+11x+5.6

(since x1.x1=x1+1 and combining like terms of x

The= x2+11x+30

The product can be viewed as

5.6=6+6+6+6+6
=12+12+6
=30

The final multiplied expression is: (a+8)(a+9) = a2 + 17a + 72

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 1 Page 16 Exercise 8 Answer

Question: Find The Product of the Expressions (z+3)(z+3)

Solution:

Given product expression: (z+3)(z+3)

To multiply the binomials (z+3) and (z+3) and write its product.

Now we multiply out each term of one polynomial to another polynomial:

Given product expression: (z+3)(z+3)

(z+3)(z+3)=z(z+3)+3(z+3)
=z.z+3z+3z+3.3

(using distributive law)

=za²+6z+9

(since z¹.z¹=z¹+1 combing like terms of z)

=z²+6.z+9

The product can be viewed as

3.3=3+3+3
=6+3
=9

The final multiplied expression is: (z+3)(z+3) = z2 + 6z + 9

Page 16 Exercise 1 Answer

Question: Find The Product of the Expressions (x−4)(x−5)

Solution:

Given the product expression: (x−4)(x−5)

Multiply the binomials (x−4) and (x−5) and find the product value.

Now we multiply out each term of one polynomial to another polynomial:

Given that product expression:(x-4)(x-5)
(x-4)(x-5)=x(x-5)-4(x-5)
=x.x-5x-4x+(-4).(-5)

(using  distributive law)

=x2-9x+(-4)++.(-5)(combing like terms)

=x2-9x+20

The product can be viewed as:

(-4).(-5)=4.5

=5+5+5+5
=10+10
=20

The expanded form of the product can be viewed as (x−4)(x−5) = x2 − 9x + 20

Key To Algebra Book 4 Multiplying And Factoring Polynomials Answers

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 1 Page 16 Exercise 2 Answer

Question: Find The Product of the Expressions (x−2)(x−4)

Solution:

Given product expression : (x−2)(x−4)

Multiply the binomials (x−4) and (x−2) and write their product value.

Now we multiply out each term of one polynomial to another polynomial:

Given Product expression: (x-2)(x-4)

(x-2)(x-4)=x(x-4)-2(x-4)
=x.x-4x-2x+(-2).(-4)
(using distributive law)

=x²-6x+(-2).(-4)

(combining like terms)

=x2-6x+8

the product can be viewed as

(-2).(4)=2.4
=4+4
=8

The expanded form of the product is: (x−2)(x−4) = x2 − 6x + 8

Page 16 Exercise 3 Answer

Question: Find The Product of the Expressions (x−3)(x−5)

Solution:

Given the product expression: (x−3)(x−5)

Multiply the binomials (x−3) and (x−5) and write the value of the product.

Now we multiply out each term of one polynomial to another polynomial:

Given Product Expession: (x-3)(x-5)
(x-3)(x-5)=x(x-5)-3(x-5)
=x.x-5x-3x+(-3).(-5)

(using distributive law)

= x2-8x+(-3).(-5)

(combining like terms)

=x2-8x+15

the product can be viewed as:

(-3).(-5)=3.5

=5+5+5
=10+5
=15

The expanded form of the product is: (x−3)(x−5) = x2 − 8x + 15

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 1 Page 16 Exercise 4 Answer

Question: Find The Product of the Expressions (x−6)(x−6)

Solution:

Given product expression: (x−6)(x−6)

Multiply the binomials (x−6) and (x−6) and write the product value.

Now we multiply out each term of one polynomial to another polynomial:

Given product expression:(x-6)(x-6)
(x-6)(x-6)=x(x–6)-6(x-6)
=x.x-6x-6x+(-6).(-6)
(using distributive law)
=x2-12x+(-6).(-6)
(combing like terms)
=x2-12x+36
the product can be viewed as:

(-6).(-6)=6.6
=6+6+6+6+6+6
=12+12+12
=24+12
=36

The expanded form of the product is: (x−6)(x−6) = x2 − 12x + 36

Page 16 Exercise 5 Answer

Question: Find The Product of the Expressions (x−1)(x−8)

Solution:

Given the product expression: (x−1)(x−8)

Multiply the binomials (x−1) and (x−8) and write the product value.

Now we multiply out each term of one polynomial to another polynomial:

Given product expression: (x-1)(x-8)

(x-1)(x-8)= x(x-8)-1(x-8)
=x.x-8x-x+(-1).(x-8)
(using distributive law)
=x2-9x+8
(combining like terms)
the product can be viewed as:
(-1).(-8)=8.1
=8

= 8 (Since the product of any number with 1 is the number itself)

The expanded form of the product is: (x−1)(x−8) = x2 − 9x + 8

Page 16 Exercise 6 Answer

Question: Find The Product of the Expressions (x−7)(x+3)

Solution:

Given the product expression: (x−7)(x+3)

Multiply the binomials (x−7) and (x+3) and write the product value.

Now we multiply out each term of one polynomial to another polynomial:

Given:(x-7)(x+3)
(x-7)(x+3)=x(x+3)-7(x+3)
=x.x+3x-7x+3.(-7)
(using the distributive law)
=x2-4x+3.(-7)
(combining like terms)
=x2-4x-21
The product can be viewed as:

3.(-7)=-7-7-7
=-14-7
=-21

The expanded form of the product is : (x−7)(x+3) = x2 − 4x − 21

Chapter 8 Multiplying And Factoring Polynomials Mcgraw Hill Key

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 1 Page 16 Exercise 7 Answer

Question: Find The Product of the Expressions (x−5)(x+3)

Solution:

Given the product expression: (x−5)(x+3)

Multiply the binomials (x−5) and (x+3) and write its product value.

Now we multiply out each term of one polynomial to another polynomial:

Given: (x-5)(x+3)
(x-5)(x+3)=x(x+3)-5(x+3)
=x.x+3x-5x+(-5).3
(using distributive law)
=x2-2x+(-5).3
(combining like terms)
=x2-2x-15
the product can be viewed as:

3.(-5)=-5-5-5
=-10-5
=-15

The expanded product can be written as: (x−5)(x+3) = x2 − 2x − 15

Page 16 Exercise 8 Answer

Question: Find The Product of the Expressions (x+2)(x−6)

Solution:

Given product expression: (x+2)(x−6)

Multiply the binomials (x+2) and (x−6) and write its product value.

Now we multiply out each term of one polynomial to another polynomial:

Given product expression: (x+2)(x-6)
(x+2)(x-6)=x(x-6)+2(x-6)
=x.x-6x+2x+(2).(-6)
(using the distributive property)

= x2-4x+2.(-6)

The product can be viewed as:

2.(-6)=-6-6
=-12

The expanded form of the product: (x+2)(x−6) = x2 − 4x − 12

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 1 Page 16 Exercise 9 Answer

Question: Find The Product of the Expressions (x+8)(x−5)

Solution:

Given product expression: (x+8)(x−5)

Multiply the binomials (x+8) and (x−5) and write its value.

Now we multiply out each term of one polynomial to another polynomial:

Given Product expression:(x+8)(x-5)

(x+8)(x-5)=x(x-5)+8(x-5)
=x.x-5x+8x+8.(-5)
(using the distributive property)
=x2-3+8.(-5)
(combining like terms)

=x2-3x-40

The product can be viewed as:

8.(-5)=-5-5-5-5-5-5-5-5
=-10-10-10-10
=-20-20
=-40

The product in the expanded form is: (x+8)(x−5) = x2 + 3x − 40

Page 16 Exercise 10 Answer

Question: Find The Product of the Expressions (x−8)(x+5)

Solution:

Given product expression: (x−8)(x+5)

Multiply the binomials (x−8) and (x+5) and write its value.

Now we multiply out each term of one polynomial to another polynomial:

Given product expression: (x-8)(x+5)

The expanded form of the product is: (x−8)(x+5) = x2 − 3x − 40

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 1Page 17 Exercise 1 Answer

Question: Find The Product of the Expressions (x+3)(x+2)

Solution:

Given product expression: (x−3)(x−2)

To multiply the binomials (x−2) and (x−3) and write the value.

Now we multiply out each term of one polynomial to another polynomial:

Given product expression: (x-3)(x-2)
(x-3)(X-2)=x(x-2)-3(x-2)
=x.x-2x-3x+(-3).(-2)
=x.x-2x-3x+(-3).(-2)
(using distributive property)
=x2-5x+(-3).(-2)

(combining like terms)

=x2-5x+6

The product can be viewed as
(-3).(-2)=3.2
=3+3
=6

The expanded form of the product is: (x−3)(x−2) = x2 − 5x + 6

Page 17 Exercise 2 Answer

Question: Find The Product of the Expressions (x−1)(x−1)

Solution:

Given product expression: (x−1)(x−1)

To multiply the binomials (x−1) and (x−1) and write the value.

Now we multiply out each term of one polynomial to another polynomial:

Given product expression: (x-1)(x-1)

(x-1)(x-1)=x(x-1)-1(x-1)
x.x-x-x+(-1)(-1)
(using the distributive property)

=x2-2x+1

(combining like terms)

The product can be viewed as:

(-1).(-1)=1.1
=1

The expanded form of the product is: (x−1)(x−1) = x2 − 2x + 1

Page 17 Exercise 3 Answer

Question: Find The Product of the Expressions (x−7)(x−2)

Solution:

Given the product expression: (x−7)(x−2)

To multiply the binomials (x−7) and (x−2) and write its value.

Now we multiply out each term of one polynomial to another polynomial:

Given the product expression:(x-7)(x-2)
(X-7(x-2)=x(x-2)-7(x-2)
=x.x-2x-7x+(-7)(-2)
(using distributive property)
=x²-9x+(-7)(-2)
(combining like terms)

=x²-9x+14

The product can be viewed as:

(-7).(-2)=7.2
=7+7
=14

The expanded form of the product is: (x−7)(x−2) = x2 − 9x + 14

How To Solve Chapter 8 Multiplying And Factoring Polynomials Key To Algebra Book 4

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 1 Page 17 Exercise 4 Answer

Question: Find The Product of the Expressions (x−3)(x−4)

Solution:

Given the product expression: (x−3)(x−4)

To multiply the binomials (x−3) and (x−4) and write its value.

Now we multiply out each term of one polynomial to another polynomial:

Given the product expression: (x-3)(x-4)

(x-3)(x-4)=x(x-4)-3(x-4)
=x.x-4x-3x+(-3).(-4)

(using distributive law)

=x2-7x+12(combining like terms)

The product can be viewed as:

(-3).(-4)=3.4
=4+4+4
=8+4
=12

The expanded form of the product is: (x−3)(x−4) = x2 − 7x + 12

Page 17 Exercise 5 Answer

Question: Find The Product of the Expressions (x+8)(x−3)

Solution:

Given the product expression: (x+8)(x−3)

Multiply the binomials (x+8) and (x−3) and write its value.

Now we multiply out each term of one polynomial to another polynomial:

Given the product expression:(x+8)(x-3)
(x+8)(x-3)=x(x-3)+8(x-3)
=x.x-3x+8x+8(-3)
(using distributive law)

=x²+5x-24(combining like terms)

The product can be viewed as:

8.(-3)=-3-3-3-3-3-3-3-3

=-6-6-6-6
=-12-12
=-24

The expanded form of the product is: (x+8)(x−3) = x2 + 5x − 24

Mcgraw Hill Algebra Book 4 Chapter 8 Explanations

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 1 Page 17 Exercise 6 Answer

Question: Find The Product of the Expressions (x+5)(x−2)

Solution:

Given product expression: (x+5)(x−2)

To multiply the binomials (x+5) and (x−2) and write its value.

Now we multiply out each term of one polynomial to another polynomial:

Given product expression:(x+5)(x-2)
(x+5)(x-2)=x(x-2)+(x-2)
=x.x-2x+5x+5.(-2)
(using distributive law)
=x2+3x-10 (combining like terms)
The product can be viewed as:

5.(-2)=-2-2-2-2-2
-4-4-2

The expanded form of the product is: (x+5)(x−2) = x2 + 3x − 10

Page 17 Exercise 7 Answer

Question: Find The Product of the Expressions (a−4)(a−6)

Solution:

We have given:

(a−4)(a−6)

We have to find the above product.

We will multiply the above two expressions to find the resultant polynomial.

Given rectangle length =x+4

Breadth=x-2

A=lxw
we have, l=x+4
w=x-2
The area of a rectangle is A=lxw

\(\begin{aligned}
A & =(x+4)(x-2) \\
& =x^2-2 x+4 x-8 \\
& =x^2+2 x-8
\end{aligned}\)

This is a quadratic polynomial.

The multiplication (a−4)(a−6) is equal to a2 − 10a + 24.

Page 17 Exercise 10 Answer

Question: Find The Product of the Expressions (x+4)(x−4)

Solution:

We have given:

(x+4)(x−4)

We have to find the above product.

We will use the identity

(a+b)(a−b) = a2 − b2 to find the resultant polynomial.

Given: (a-4)(a-6)

multiply the expressions

(a-4)(a-6)

multiply the expressions

(a-4)(a-6)

=a(a-6)-4(a-6)
=a(a-6)-4(a-6)
=a2-6a-4a+24
=a2-10a+24

This is the required quadratic polynomial.

The product(x+4)(x−4) is equal to x2 − 16.

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 1 Page 17 Exercise 12 Answer

Question: Find The Product of the Expressions (x−3)(x+4)

Solution:

We have given:

(x−3)(x+4)

We have to find the above product.

We will multiply the above two expressions to find the resultant polynomial.

Given:(x-3)(x+4)

multiply the expressions

(x-3)(x+4)

=x(x+4)-3(x+4)

=x²+4x-3x-12

=x²+x-12

This is the required polynomial.

The product(x−3)(x+4)​ is equal to x2 + x − 12.

Page 17 Exercise 14 Answer

Question: Find The Product of the Expressions (x−6)(x+6)

Solution:

We have given:

(x−6)(x+6)

We have to find the above product.

We will use the identity(a−b)(a+b) = a2 − b2 here and find the resultant polynomial.

(x-6)(x+6) multiply the expressions:

(x-6)(x+6)

=x²-6²

(since(x-a)(x+a)=x2-a2]

=x²-36

This is the resultant polynomial.

The product(x−6)(x+6) is equal to x2 − 36.

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 1 Page 17 Exercise 15 Answer

Question: Find The Product of the Expressions (y+3)(y−3)

Solution:

We have given:

(y+3)(y−3)

We have to find the above product.

We will multiply the above two expressions to find the resultant polynomial.

Given:(y+3)(y-3)

⇒ multiply the expressions

(y+3)(y-3)

=y(y-3)+3(y-3)
=y²-3y+3y-9
=y²-9

This is the resultant quadratic polynomial.

The product (y+3)(y−3) is equal to y2 − 9.

Page 17 Exercise 16 Answer

Question: Find The Product of the Expressions (x+9)(x−2)

Solution:

Given:

(x+9)(x−2)

We have to find the above product.

We will multiply the above two expressions to find the resultant polynomial.

Given: (x+9)(X-2)

Multiply the expressions

(x+9)(x-2)
=x(x-2)+9(x-2)
=x²-2x+9x-18
=x²+7x-18

This is the required polynomial.

The product(x+9)(x−2) gives a quadratic polynomial x2 + 7x − 18.

Solutions For Multiplying And Factoring Polynomials Chapter 8 Key To Algebra Book 4

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 1 Page 17 Exercise 1 Answer

Question: Find The Product of the Expressions (x+5)

Solution:

We have given a binomial:

(x+5)

We have to calculate(x+5)2.

We will calculate the resultant polynomial by using the identity

(a+b)2 = a2 + 2ab + b2

Given binomial:(x+5)2

(x+5)2

Here, a=x,b=5

∴(x+5)2=x2+2(x)(5)+4=52
[since(a+b)²=a²+2ab+b²]
=x2²+10x+25

This is the required polynomial.

(x+5)2 gives a quadratic polynomial x2 + 10x + 25.

Page 17 Exercise 2 Answer

Question: Find The Product of the Expressions (x+4)

Solution:

We have given a binomial:

(x+4)

We have to calculate (x+4)2.

We will calculate the resultant polynomial by using the identity:

(a+b)2 = a2 + 2ab + b2

Given binomial: (x+4)2

(x+4)2

Here a=x, b=4

∴ (x+4)²= x²+2(x)(4)+4²

[Since (a+b)²=a²+2ab+b²]
=x²+8x+16

This is the resultant quadratic polynomial.

(x+4)2 gives a quadratic polynomial x2 + 8x + 16.

Page 17 Exercise 3 Answer

Question: Find The Product of the Expressions x + 10

Solution:

We have given a binomial:

x + 10

We have to calculate (x+10)2.

We will calculate the resultant polynomial by using the identity:

(a+b)2 = a2 + 2ab + b2

(x+10)2

here a=x,b=10

∴ (x+10)² =x2+2(x)(10)+100

(since) (a+b)²=a²+2ab+b²]
=x²+20x+100

This is the resultant polynomial.

(x+10)2 gives a quadratic polynomial x2 + 20x + 100.

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 1 Page 17 Exercise 4 Answer

Question: Find The Product of the Expressions x−5

Solution:

We have given a binomial:

x−5

We have to calculate (x−5)2.

We will find the resultant polynomial by using the identity:

(a−b)2 = a2 − 2ab + b2

Given binomial:(x-5)²

(x-5)²

Here a=x,b=5

using the algebraic identity

\(\begin{aligned}
(a-b)^2 & =a^2-2 a b+b^2 \\
(x-5)^2 & =x^2-2(x)(5)+25 \\
& =x^2-10 x+25
\end{aligned}\)

This is the required polynomial.

(x−5)2 gives a quadratic polynomial x2 − 10x + 25.

Page 17 Exercise 6 Answer

Question: Find The Product of the Expressions (x−1)2

Solution:

Given expression is (x−1)2

We have to multiply binomial (x−1) to binomial (x−1)

The result of the multiplication of two binomial is polynomial.

Given binomial:(x-5)2

(x-5)2

Here a=x, b=5

Using the algebraic identity

⇒ \(\begin{aligned}
(a-b)^2 & =a^2-2 a b+b^2 \\
(x-5)^2 & =x^2-2(x)(5)+25 \\
& =x^2-10 x+25
\end{aligned}\)

Page 18 Exercise 1 Answer

Question: Find the area of the rectangle whose length l = x + 4 and width w = x − 2.

Solution:

We have given a rectangle having length l = x + 4 and width w = x − 2.

We have to find the area A of the rectangle.

A = l × w

Here area is a multiplication of two binomial.

Given rectangle length=x+4
breadth=x-2

A=lxw
we have, l=x+4

The area of the rectangle is a =lxw

⇒ \(\begin{aligned}
A & =(x+4)(x-2) \\
& =x^2-2 x+4 x-8 \\
& =x^2+2 x-8
\end{aligned}\)

The area of the rectangle having length (x+4) and width (x-2) is x2 + 2x – 8.

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 1 Page 18 Exercise 2 Answer

Question: Find the area of the rectangle whose length l = x + 7 and width w = x − 4.  

Solution:

We have given a rectangle having length l = x + 7 and width w = x − 4.

We have to find the area A of the rectangle.

A = l × w

Here area is the multiplication of two binomials.

Area of rectangle a=lxw

we have, l=x+7

w=x-4

A=(x+7)(x-4)

The area of a rectangle having length x + 7 and width x − 4 is x2 + 3x − 28.

Page 18 Exercise 4 Answer

Question: Find the area of the rectangle whose length l = x + 3 and width w = x + 3.

Solution:

We have given a rectangle having length l = x + 3 and width w = x + 3.

We have to find the area A of the rectangle.

A = l × w

Here area is the multiplication of two binomials.

Area of rectangle A= l×w

we have, l=x+3

w=x+3

A=(x+3)(x+3)

=x²+3x+3x+9

=x²+6x+9

The area of rectangle having length (x+3) and width (x+3) is x2 + 6x + 9

Page 18 Exercise 5 Answer

Question: Find the area Of the rectangle whose length l = (x+6) and width w = x − 1

Solution:

We have given rectangle having length l = (x+6) and width w = x − 1

We have to find the area A of the rectangle.

A = l × w

To find the area of a rectangle we have to multiply the two binomials.

Area of rectangle A=l×w

we have, l= x+6

w=x-1

A=(x+6)(x-1)

=x²-x+6x-6

=x²+5x-6

The area of a rectangle having length l = x + 6 and width w = (x−1) is x2 + 5x − 6.

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 1 Page 19 Exercise 2 Answer

Question: Find the factors of the equation x2 + 21x + 20 = (x+…)(x+..).

Solution:

We have been given a trinomial that x2 + 21x + 20 = (x+…)(x+..).

We have to fill in each pair of blanks with the right numbers and we have to check our answers.

We will find the result using the factorization method.

The given Trinomial is, x2+21x+20
Factoring out, we get

⇒ \(\begin{aligned}
x^2+21 x+20 & =x^2+x+20 x+20 \\
& =x(x+1)+20(x+1) \\
& =(x+1)(x+20)
\end{aligned}\)

Now let us check answers by multiplying the binomial

(x+1)(x+20)=x.x+20x+x+20

x²+21x+20

We have factorized and filled in the blanks with the right numbers that are, x2 + 21x + 20 = (x+1)(x+20), and checked our answers

Page 19 Exercise 3 Answer

Question: Find the factors of the polynomial x2 + 12x + 20

Solution:

Given expression is x2 + 12x + 20

We have to factorize the polynomial.

We have, x2 + 12x + 20

The factor of 20 adds up to 12 is 10 and 2.

Given expression: x²+12x+20

Factoring out, we get

⇒ \(\begin{aligned}
x^2+12 x+20 & =x^2+10 x+2 x+20 \\
& =x(x+10)+2(x+10) \\
& =(x+2)(x+10)
\end{aligned}\)

Re check:

By using multiplying the binomial

\(\begin{aligned}
(x+2)(x+10) & =x \cdot x+2 x+10 x+20 \\
& =x^2+12 x+20
\end{aligned}\)

Hence it is proved that the factors of polynomials are right.

We have factorized the polynomial as x2 + 12x + 20 = (x+10)(x+2)

We have checked the factors of the polynomial.

Page 19 Exercise 4 Answer

Question: Find the factors of the polynomial x2 + 14x + 24

Solution:

Given expression x2 + 14x + 24

We have to factorize the polynomial.

We have, x2 + 14x + 24

The factor of 24 that add up to 14 is 2, 12

Given expression: x²+14×24

Factoring out, we get

⇒ \(\begin{aligned}
x^2+14 x+24 & =x^2+2 x+12 x+24 \\
& =x(x+2)+12(x+2) \\
& =(x+12)(x+2)
\end{aligned}\)

Re-check the answer:

By multiplying the binomial

⇒ \(\begin{aligned}
(x+12)(x+2) & =x^2+2 x+12 x+24 \\
& =x^2+14 x+24
\end{aligned}\)

Hence the factors of polynomials are right.

We have factorized the polynomial as : x2 + 14x + 24 = (x+2)(x+12)

Worked Examples For Chapter 8 Multiplying And Factoring Polynomials Mcgraw Hill

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 1 Page 19 Exercise 5 Answer

Question: Find the factors of the polynomial x2 + 9x + 20

Solution:

Given expression x2 + 9x + 20

We have to factorize the polynomial.

We have , x2 + 9x + 20

The factor of 20 which add up to 9 are 5 and 4.

Given expression: x²+9x+20

Factoring out, we get

\(\begin{aligned}
x^2+9 x+20 & =x^2+5 x+4 x+20 \\
& =x(x+5)+4(x+5) \\
& =(x+4)(x+5)
\end{aligned}\)

Rechexking the answer:

by using multiplying the binomial

(x+4)(x+5)x2+4x+-5x+20
=x2+9x+20

Hence the factors of polynomials are right.

We have factorized the polynomial as : x2 + 9x + 20 = (x+4)(x+5)

Page 20 Exercise 4 Answer

Question: Find the factors of the second-order degree polynomial x2 + 7x + 10

Solution:

Given that the second-degree polynomial is, x2 + 7x + 10

Here we have to factor the given polynomial into a product of two binomials.

Factorization rule :

Group the first two terms together and then the last two terms together.

Factor out a GCF from each separate binomial.

Factor out the common binomial.

Note that if we multiply our answer out, we do get the original polynomial.

Given expression: x2+7x+10
factoring out, we get

\(\begin{aligned}
x^2+7 x+10 & =x^2+5 x+2 x+10 \\
& =x(x+5)+2(x+5) \\
& =(x+2)(x+5)
\end{aligned}\)

Rechecking the answer:

By multiplying the binomial

(X+2)(x+5)=x²+5x+2x+10

=x²+7x+10

The factorization of the polynomial into a product of two binomials is x2 + 7x + 10 = (x+5)(x+2).

Page 20 Exercise 7 Answer

Question: Find the factors of the second-order degree polynomial x2 + 5x + 4

Solution:

Given that the second-order degree polynomial is, x2 + 5x + 4

Here we have to factor the given polynomial into a product of two binomials.

Factorization rule :

Group the first two terms together and then the last two terms together.

Factor out a GCF from each separate binomial.

Factor out the common binomial.

Note that if we multiply our answer out, we do get the original polynomial.

Given expression: x2+5x+4

Factoring out, we get

x2+5x+4=x2+x+4x+4
=x(x+1)+4(x+1)
=(x+4)(x+1)

Rechecking the answers:

By multiplying the binomial

(x+4)(x+1)=x2+x+4x+4
=x2+5x+4

The factorization of the polynomial into a product of two binomials is: x2 + 5x + 4 = (x+1)(x+4).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 8 Multiplying And Factoring Polynomials 1 Page 20 Exercise 8 Answer

Question: Find the factors of the second-order degree polynomial x2 + 2x + 1

Solution:

Given that the second-order degree polynomial is, x2 + 2x + 1

Here we have to factor the given polynomial into a product of two binomials.

Factorization rule :

Group the first two terms together and then the last two terms together.

Factor out a GCF from each separate binomial.

Factor out the common binomial.

Note that if we multiply our answer out, we do get the original polynomial.

Given expression: x2+2x+1
Factoring out, we get

\(\begin{aligned}
x^2+2 x+1 & =x^2+x+x+1 \\
& =x(x+1)+1(x+1) \\
& =(x+1)(x+1) \\
& \quad \text { or } \\
& =(x+1)^2
\end{aligned}\)

Check:

Now consider the binomial

⇒ \(\begin{aligned}
(x+1)(x+1) & =x^2+x+x+1 \\
& =x^2+2 x+1
\end{aligned}\)

The factorization of the polynomial into a product of two binomials is: x2 + 2x + 1 = (x+1)(x+1).

Page 20 Exercise 9 Answer

Question: Find the factors of the second-order degree polynomial x2 + 3x + 2

Solution:

Given that the second-order degree polynomial is, x2 + 3x + 2

Here we have to factor the given polynomial into a product of two binomials.

Factorization rule :

Group the first two terms together and then the last two terms together.

Factor out a GCF from each separate binomial.

Factor out the common binomial.

Note that if we multiply our answer out, we do get the original polynomial.

Given Expression: x2+3x+2

factoring out, we get

x2+3x+2=x2+x+2x+2
=x(x+1)+2(x+1)
=(x+2)(x+1)

Check: 

Now consider the binomial

⇒ \(\begin{aligned}
(x+2)(x+1) & =x^2+x+2 x+2 \\
& =x^2+3 x+2
\end{aligned}\)

The factorization of the polynomial into a product of two binomials is: x2 + 3x + 2 = (x+1)(x+2).

Page 20 Exercise 10 Answer

Question: Find the factors of the second-order degree polynomial x2 + 13x + 36

Solution:

Given that the second-order degree polynomial is x2 + 13x + 36

Here we have to factor the given polynomial into a product of two binomials.

Factorization rule :

Group the first two terms together and then the last two terms together.

Factor out a GCF from each separate binomial.

Factor out the common binomial.

Note that if we multiply our answer out, we do get the original polynomial.

Given expression: x2+13x+36
factoring out, we get

⇒ \(\begin{aligned}
x^2+13 x+3 & =x^2+4 x+9 x+36 \\
& =x(x+4)+9(x+4) \\
& =(x+9)(x+4)
\end{aligned}\)

check:

Now consider the binomial

(x+9)(x+4)=x2+4x+9x+36
=x2+13x+36

The factorization of the polynomial into a product of two binomials is x2 + 13x + 36 = (x+4)(x+9).

Question: Find the factors of the second-order degree polynomial x2 + 12x + 36

Solution:

Given that the second-order degree polynomial is x2 + 12x + 36

Here we have to factor the given polynomial into a product of two binomials.

Factorization rule :

Group the first two terms together and then the last two terms together.

Factor out a GCF from each separate binomial.

Factor out the common binomial.

Note that if we multiply our answer out, we do get the original polynomial.

Given polynomial: x2+12x+36
factoring out, we get

\(\begin{aligned}
x^2+12 x+36 & =x^2+6 x+6 x+36 \\
& =x(x+6)+6(x+6) \\
& =(x+6)(x+6)
\end{aligned}\)

or

=(x+6)²

Check:

Now consider the binomial

(x+6)(x+6)= x²+6x+6x+36

=x²+12x+36

The factorization of the polynomial into a product of two binomials is x2 + 12x + 36 = (x+6)(x+6).

Page 20 Exercise 13 Answer

Question: Find the factors of the second-order degree polynomial x2 + 37x + 36

Solution:

Given that the second-order degree polynomial is x2 + 37x + 36

Here we have to factor the given polynomial into a product of two binomials.

Factorization rule :

Group the first two terms together and then the last two terms together.

Factor out a GCF from each separate binomial.

Factor out the common binomial.

Note that if we multiply our answer out, we do get the original polynomial.

Given polynomial: x²+37x+36

Factoring out, we get

x2+37+36= x2+x+36x+36
=x(x+1)+36(X+1)
=(x+36)(X+1)

Check:

Now consider the binomial,

(x+36)(x+1)=x2+x+36x+36
=x2+37x+36

The factorization of the polynomial into a product of two binomials is x2 + 37x + 36 = (x+11)(x+36).

Question: Find the factors of the second-order degree polynomial x2 + 15x + 36

Solution:

Given that the second-order degree polynomial is x2 + 15x + 36

Here we have to factor the given polynomial into a product of two binomials.

Factorization rule :

Group the first two terms together and then the last two terms together.

Factor out a GCF from each separate binomial.

Factor out the common binomial.

Note that if we multiply our answer out, we do get the original polynomial.

Given polynomial: x²+15x+36

Factoring out, we get

⇒ \(\begin{aligned}
x^2+15 x+36 & =x^2+3 x+12 x+36 \\
& =x(x+3)+12(x+3) \\
& =(x+12)(x+3)
\end{aligned}\)

Check:

Now consider the binomial,

\(\begin{aligned}
(x+12)(x+3) & =x^2+3 x+12 x+36 \\
& =x^2+15 x+36
\end{aligned}\)

The factorization of the polynomial into a product of two binomials is: x2 + 15x + 36 = (x+3)(x+12).

Page 20 Exercise 15 Answer

Question: Find the factors of the second-order degree polynomial x2 + 17x + 30

Solution:

Given that the second-order degree polynomial is x2 + 17x + 30

Here we have to factor the given polynomial into a product of two binomials.

Factorization rule :

Group the first two terms together and then the last two terms together.

Factor out a GCF from each separate binomial.

Factor out the common binomial.

Note that if we multiply our answer out, we do get the original polynomial.

Given polynomial: x²+17x+30

Factoring out, we get

\(\begin{aligned}
x^2+17 x+30 & =x^2+2 x+15 x+30 \\
& =x(x+2)+15(x+2) \\
& =(x+15)(x+2)
\end{aligned}\)

Check:

Now consider the binomials

\(\begin{aligned}
(x+15)(x+2) & =x^2+2 x+15 x+30 \\
& =x^2+17 x+30
\end{aligned}\)

The factorization of the polynomial into a product of two binomials is: x2 + 17x + 30 = (x+2)(x+15).

Question: Find the factors of the second-order degree polynomial x2 + 11x + 30

Solution:

Given that the second-order degree polynomial is x2 + 11x + 30

Here we have to factor the given polynomial into a product of two binomials.

Factorization rule :

Group the first two terms together and then the last two terms together.

Factor out a GCF from each separate binomial.

Factor out the common binomial.

Note that if we multiply our answer out, we do get the original polynomial.

Given Polynomial: x²+11x+30

Factoring out, we get

\(\begin{aligned}
x^2+11 x+30 & =x^2+5 x+6 x+30 \\
& =x(x+5)+6(x+5) \\
& =f(x+6)(x+5)
\end{aligned}\)

Check:

Now consider the binomial:

(x+6)(x+5)=x²+5x+6x+30

=x²+11x+30

The factorization of the polynomial into a product of two binomials is x2 + 11x + 30 = (x+5)(x+6).

Page 20 Exercise 17 Answer

Question: Find the factors of the second-order degree polynomial x2 + 13x + 30

Solution:

Given that the second-order degree polynomial is x2 + 13x + 30

Here we have to factor the given polynomial into a product of two binomials.

Factorization rule:

Group the first two terms together and then the last two terms together.

Factor out a GCF from each separate binomial.

Factor out the common binomial.

Note that if we multiply our answer out, we do get the original polynomial.

Given polynomial: x2+13x+30
Factoring out, we get

\(\begin{aligned}
x^2+13 x+30 & =x^2+10 x+3 x+30 \\
& =x(x+10)+3(x+10) \\
& =(x+3)(x+10)
\end{aligned}\)

Check:

Now consider the binomial:

(x+10)(x+3)= x²+3x+10x+30

=x²+13x+30

The factorization of the polynomial into a product of two binomials is: x2 + 13x + 30 = (x+10)(x+3).

Page 20 Exercise 18 Answer

Question: Find the factors of the second-order degree polynomial x2 + 31x + 30

Answer: 

Given: x2 + 31x + 30

To find: factorize each into a product of two binomials.

x²+31x+30

First factorizing as 30 many different ways

we can 30×1, 15×2, 10×3

While testing the combinations, 30×1

So,

x²+31x+30

⇒ x²+x+30x+30

⇒x(x+1)+30(x+1)

⇒(x+1)(x+30)

finally, x²+31x+30=(x+1)(x+30)

Thus, the factorization of the second degree polynomial x2 + 31x + 30 into a product of two binomials is (x+1)(x+30)

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor

Question: Factorize the polynomial 6a−30

Solution:

Given expression is 6a−30

We find factors of the given polynomial

We take out common from the given expression 3 goes into both 6 and 30, so we factor out 3

6a − 30 = 3(2a−10)

The factorization of the given polynomial is 3(2a−10)

Question: Factorize the polynomial 6a−30

Solution:

Given expression is 6a−30

We find factors of a given polynomial

We take out common from the given expression.

6 goes into both 6,30, we take that out as common 6a − 30 = 6(a−5)

The factorization of the given polynomial is 6(a−5)

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor

Question: Factorize the polynomial 6a−30

Solution:

Given expression is 6a−30

We find factors of a given polynomial

We take out common from the given expression.

2 goes into both 6,30, we take that out as common 6a − 30 = 2(3a−15​)

The factorization of the given polynomial is 2(3a−15)

Mcgraw Hill Key To Algebra Book 4 Chapter 6 Solutions

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor Page 11 Exercise 5 Answer

Question: Factorize the polynomial 18x−27

Solution:

Given expression is 18x−27

We find factors of a given polynomial

We take out common from the given expression.

9 goes into both 18,27, we take that out as common 18x − 27 = 9(2x−3)

The factorization of the given polynomial is 9(2x−3)

Question: Factorize the polynomial 4x−32

Solution:

Given expression is 4x−32

We find factors of a given polynomial

We take out common from the given expression.

4 goes into both 4,32, we take that out as common 4x − 32 = 4(x−8)

The factorization of the given polynomial is 4(x−8)

Question: Factorize the polynomial 8y−10

Solution:

Given expression is 8y−10

We find factors of a given polynomial

We take out common from the given expression.

2 goes into both 8,10, we take that out as common 8y − 10 = 2(4y−5)

The factorization of the given polynomial is 2(4y−5)

Question: Factorize the polynomial 5x − 5y + 10z

Solution:

Given expression is 5x − 5y + 10z

We find factors of a given polynomial

We take out common from the given expression.

5 goes into both 5,10, we take that out as common 5x − 5y + 10z = 5(x−y+2z)

The factorization of the given polynomial is 5(x−y+2z)

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor Page 11 Exercise 10 Answer

Question: Factorize the polynomial 7x − 7y − 7z

Solution:

Given polynomial is 7x − 7y − 7z

We find factors of a given polynomial

We factorize the given expression.

HCF of 7x,7y,7z is 7,we take that out as common 7x − 7y − 7z = 7(x−y−z)

Factorization of the given polynomial is 7(x−y−z)

Question: Factorize the polynomial 2x2 + 18x + 14

Solution:

Given polynomial is 2x2 + 18x + 14

We find factors of a given polynomial

We factorize given polynomial

HCF of 2x2,18x,14is 2,we take that out as common 2x2 + 18x + 14 = 2(x2+9x+7)

Factorization of the given polynomial is 2(x2+9x+7)

Question: Factorize the polynomial 6a − 18b + 12c

Solution:

Page 11 Exercise 14 Answer

Given polynomial is 6a − 18b + 12c

We find factors of the given polynomial

We factorize the given expression.

HCF of 6a,18b,12cis 6, we take that out as common.

6a − 18b + 12c = 6(a−3b+2c)

The factorization of given polynomial is 6(a−3b+2c)

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor Page 11 Exercise 15 Answer

Question: Factorize the polynomial 9x + 12y + 15

Solution:

Given polynomial is 9x + 12y + 15

We find the factors of a given polynomial

We factorize the given expression.

HCF of 9x,12y, and 15 is 3, we take that out as common.

9x + 12y + 15 = 3(3x+4y+5)

The factorization of the given polynomial is 3(3x+4y+5)

Page 11 Exercise 16 Answer

Question: Factorize the polynomial 8a + 12b + 4

Solution:

Given polynomial is 8a + 12b + 4

We find the factors of a given polynomial

We factorize the given expression.

HCF of 8a,12b, and 4 is 4, we take that out as common.

8a + 12b + 4 = 4(2a+3b+1)

The factorization of the given polynomial is 4(2a+3b+1)

Key To Algebra Book 4 Factoring Out A Common Factor Chapter 6 Answers

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor Page 12 Exercise 1 Answer

Question: Factorize the biggest term from the polynomial 15y + 5?

Solution:

Given the polynomial to factorize: 15y + 5

Now:

We have to factorize this polynomial by factoring out the biggest terms out of the polynomial as per Sandy’s way.

15y+5=5(3y+1)

Now we see that:

15y+5=5(3y+1)

⇒ \(\frac{15 y}{5}=3 y\)

\(\frac{5}{5}=1\)

Here 5 is the biggest single term that can be taken out as a factor as it is the greatest term that is a factor of 15y,5.

The polynomial after factoring out the biggest term is as follows: 15y + 5 = 5(3y+1)

Page 12 Exercise 2 Answer

Question: Factorize the biggest term from the polynomial 7a + 7?

Solution:

Given expression: 7a + 7

Now:

We have to factorize this polynomial by factoring out the biggest terms out of the polynomial as per Sandy’s way.

Given expression: 7a+7
Now we see that:
7a+7=7(a+1)

⇒ \(\begin{aligned}
& \frac{7 a}{7}=a \\
& \frac{7}{7}=1
\end{aligned}\)

Here 7 is the biggest single term that can be taken out as a factor as it is the greatest term that is a factor of 7a,7

The polynomial after factoring out the biggest term is as follows: 7a + 7 = 7(a+1)

Page 12 Exercise 4 Answer

Question: Factorize the biggest term from the polynomial 5 + 20x?

Solution:

Given expression: 5 + 20x

Now:

We have to factorize this polynomial by factoring out the biggest terms out of the polynomial as per Sandy’s way.

5+20x ( factorizing the expression )

5+20x=5(1+4x)
Now we see that:

⇒ \(\begin{aligned}
& \frac{20 x}{5}=4 x \\
& \frac{5}{5}=1
\end{aligned}\)

Here 5 is the biggest single term that can be taken out as a factor as it is the greatest term that is a factor of 5,20x

The polynomial after factoring out the biggest term is as follows: 5 + 20x = 5(1+4x)

Page 12 Exercise 5 Answer

Question: Factorize the biggest term from the polynomial 6x − 2?

Solution:

Given expression: 6x − 2

Now:

We have to factorize this polynomial by factoring out the biggest terms out of the polynomial as per Sandy’s way.

6x-2

Factorizing the expression

6x-2=2(3x-1)

Now we see that:

\(\begin{aligned}
& \frac{6 x}{2}=3 x \\
& \frac{2}{2}=1
\end{aligned}\)

Here 2 is the biggest single term that can be taken out as a factor as it is the greatest term that is a factor of 6x,2

The polynomial after factoring out the biggest term is as follows: 6x − 2 = 2(3x−1)

Mcgraw Hill Factoring Solutions Chapter 6 Key To Algebra

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor Page 12 Exercise 6 Answer

Question: Factorize the biggest term from the polynomial 14n + 21p + 7?

Solution:

Given expression: 14n + 21p + 7

Now:

We have to factorize this polynomial by factoring out the biggest terms out of the polynomial as per Sandy’s way.

14n+21p+7

Factorizing the expression:

14n+21p+7=7(2n+3p+1)

Now we see that:

⇒ \(\begin{aligned}
\frac{14 n}{7} & =2 n \\
\frac{21 p}{7} & =3 p \\
\frac{7}{7} & =1
\end{aligned}\)

Here 7 is the biggest single term that can be taken out as a factor as it is the greatest term that is a factor of 14n,21p,7

The polynomial after factoring out the biggest term is as follows: 14n + 21p + 7 = 7(2n+3p+1)

Page 12 Exercise 7 Answer

Question: Factorize the polynomial 9x − 18y + 3

Solution:

Given expression: 9x − 18y + 3

Factorizing the expression

9x-18y+3=3(3x-6y+1)

Now we see that: 

⇒ \(\begin{aligned}
& \frac{9 x}{3}=3 x \\
& \frac{18 y}{3}=6 y \\
& \frac{3}{3}=1
\end{aligned}\)

We have to factorize this polynomial by factoring out the biggest terms out of the polynomial as per Sandy’s way.

Here 3 is the biggest single term that can be taken out as a factor as it is the greatest term that is a factor of 9x,18y,3

The polynomial after factoring out the biggest term is as follows: 9x − 18y + 3 = 3(3x−6y+1)

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor Page 12 Exercise 8 Answer

Question: Factorize the biggest term from the polynomial11 − 22a + 44b?

Solution:

Given expression: 11 − 22a + 44b

Now:

We have to factorize this polynomial by factoring out the biggest terms out of the polynomial as per Sandy’s way.

11-22a+44b

Factorizing the expression:

11-22a+44b=11(1-2a+4b)
Now we see that:

\(\begin{aligned}
& \frac{11}{11}=1 \\
& \frac{22 a}{11}=2 a
\end{aligned}\)

⇒ \(\frac{44 b}{11}=4 b\)

Here 11 is the biggest single term that can be taken out as a factor as it is the greatest term that is a factor of 11, 22a,44b

The polynomial after factoring out the biggest term is as follows: 11 − 22a + 44b = 11(1−2a+4b)

Page 12 Exercise 9 Answer

Question: Factorize the polynomial 5x2 + 10x + 5

Solution:

Given expression: 5x2 + 10x + 5

Now:

We have to factorize this polynomial by factoring out the biggest terms out of the polynomial as per Sandy’s way.

5x²+10x+5

Factorizing the expression:

⇒ \(\begin{aligned}
5 x^2+10 x+5 & =5\left(x^2+2 x+1\right) \\
& =5\left(x^2+x+x+1\right) \\
& =5(x(x+1)+1(x+1)) \\
& =5(x+1)^2
\end{aligned}\)

we see that:

⇒ \(\begin{aligned}
\frac{5 x^2}{5} & =x^2 \\
\frac{10 x}{5} & =2 x \\
\frac{5}{5} & =1
\end{aligned}\)

Here 5 is the biggest single term that can be taken out as a factor as it is the greatest term that is a factor of 5x2,10x,5

The polynomial after factoring out the biggest term is as follows: 5x2 + 10x + 5 = 5(x2+2x+1)

Page 12 Exercise 10 Answer

Question: Factorize the polynomial 28x2 + 28x + 7

Solution:

Given expression to factorize: 28x2 + 28x + 7

Now:

We have to factorize this polynomial by factoring out the biggest terms out of the polynomial as per Sandy’s way.

Given expression: 28×2+28x+7

Factorizing the expression:

28×2+28x+7=7(4×2+4x+1)
=7(4x²+2x+2x+1)
=7(2x(2x+1)+1(2x+1)
=7(2x+1)²

We can see that:

⇒ \(\begin{aligned}
& \frac{28 x^2}{7}=4 x^2 \\
& \frac{28 x}{7}=4 x \\
& \frac{7}{7}=1
\end{aligned}\)

Here 7 is the biggest single term that can be taken out as a factor as it is the greatest term that is a factor of 28x2,28x,7

The polynomial after factoring out the biggest term is as follows: 28x2 + 28x + 7 = 7(4x2+4x+1)

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor Page 12 Exercise 1 Answer

Question: Factorize the polynomial 24x + 28

Solution:

Given expression: 24x + 28

We need to factor out the biggest term from this expression.

Factoring out the biggest term from the expression:

Given expression: 24x+28
factorizing the expression:

24x+28=4(6x+7)
now we see that:

⇒ \(\begin{aligned}
& \frac{24 x}{4}=6 x \\
& \frac{28}{4}=7
\end{aligned}\)

Here 4 is the biggest single term that can be taken out as a factor as it is the greatest term that is a factor of 24x,28

The polynomial after factoring out the biggest term is as follows: 24x + 28 = 4(6x+7)

Page 12 Exercise 3 Answer

Question: Factorize the polynomial 40n − 24

Solution:

Given expression: 40n − 24

We need to factor out the biggest term from this expression.

Factoring out the biggest term from the expression:

Given expression: 4 on -24

Factorizing the expression:

4 on-24= 8(5n-3)

now we see that:

⇒ \(\begin{aligned}
& \frac{40 n}{8}=5 n \\
& \frac{24}{8}=3
\end{aligned}\)

Here 8 is the biggest single term that can be taken out as a factor as it is the greatest term that is a factor of 40n,24

The polynomial after factoring out the biggest term is as follows: 40n − 24 = 8(5n−3)

Page 12 Exercise 5 Answer

Question: Factorize the polynomial 18x − 30y.

Solution:

Given:

The polynomial is 18x − 30y.

To find:

The objective is to find the greatest factor among the given polynomials.

Consider the given polynomial,

18x − 30y

= 6(3x−5y) Taking GCF

Therefore, the required result is 18x − 30y = 6(3x−5y).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor Page 12 Exercise 6 Answer

Question: Factorize the polynomial 100 + 40z.

Solution:

Given:

The polynomial is 100 + 40z.

To find:

The objective is to factor the greatest number among the given polynomials.

Consider the given polynomial,

100 + 40z

= 20(5+2z) Taking GCF

Therefore, the required result is 100 + 40z = 20(5+2z).

Page 12 Exercise 7 Answer

Question: Factorize the polynomial 56x2 + 42.

Solution:

Given:

The polynomial is 56x2 + 42.

To find:

The objective is to factor the greatest number among the given polynomials.

Consider the given polynomial,

56x2 + 42

= 14(4x2+3) Taking GCF

Therefore, the required result is 56x2 + 42 = 14(4x2+3).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor Page 12 Exercise 8 Answer

Question: Factorize the polynomial 20x + 60y − 100z.

Solution:

Given:

The polynomial is 20x + 60y − 100z.

To find:

The objective is to factor the greatest number among the given polynomials.

Consider the given polynomial,

20x + 60y − 100z

= 20(x+3y−5z) Taking GCF

Therefore, the required result is 20x + 60y − 100z = 20(x+3y−5z).

Page 12 Exercise 9 Answer

Question: Factorize the polynomial 14a − 12b + 6c.

Solution:

Given:

The polynomial is 14a − 12b + 6c.

To find:

The objective is to factor the greatest number among the given polynomials.

Consider the given polynomial,

14a − 12b + 6c

= 2(7a−6b+3c) Taking GCF

Therefore, the required result is 14a − 12b + 6c = 2(7a−6b+3c).

Page 12 Exercise 10 Answer

Question: Factorize the polynomial 24 + 48x + 42x2

Solution:

Given:

The polynomial is 24 + 48x + 42x2.

To find:

The objective is to factor the greatest number among the given polynomials.

Consider the given polynomial,

24 + 48x + 42x2

= 6(4+8x+7x2) Taking GCF

Therefore, the required result is 24 + 48x + 42x2 = 6(4+8x+7x2).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor Page 12 Exercise 11 Answer

Question: Factorize the polynomial 50a − 20b + 30c.

Solution:

Given:

The polynomial is 50a − 20b + 30c.

To find:

The objective is to factor the greatest number among the given polynomials.

Consider the given polynomial,

50a − 20b + 30c

= 10(5a+2b+3c) Taking GCF

Therefore, the required result is 50a − 20b + 30c = 10(5a+2b+3c).

Page 12 Exercise 12 Answer

Question: Factorize the polynomial 6c2 + 27c − 15.

Solution:

Given:

The polynomial is 6c2 + 27c − 15.

To find:

The objective is to factor the greatest number among the given polynomials.

Consider the given polynomial,

6c2 + 27c − 15

= 3(2c2+9c−5) Taking GCF

Therefore, the required result is 6c2 + 27c − 15 = 3(2c2+9c−5).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor Page 12 Exercise 13 Answer

Question: Factorize the polynomial 12r + 36s − 60t

Solution:

Given the polynomial

12r + 36s − 60t

Here it is asked to factor out the biggest number.

We know that the factors of 12 are

12 = 1,2,3,4,6,12

and we know that the factors of 36 are

36 = 1,2,3,4,6,9,12,18,36

and we know that the factors of 60 are

60 = 1,​2,​3,​4,​5,​6,​10,​12,​15,​20,​30,​60

So here there are 6

common factors for 12,36,60.

That is

1,2,3,4,6,12

Hence here the greatest common factor is 12

So we can write that

12r + 36s − 60t = 12(r+3s−5t)

Hence the biggest number that can be factored out is 12.

Therefore, the biggest number that can be factored out is 12.

Page 13 Exercise 1 Answer

Question: Find the greatest common factor in the expression 16x − 48?

Solution:

Given the polynomial

16x − 48

Here it is asked to find the greatest common factor.

We know that the factors of 16 are

16 = 1,2,4,8,16

The factors of 48 are

48 = 1,2,3,4,6,8,12,16,24,48

So here there are 5 common factors for 16 and 48.

That is

1,2,4,8,16

Hence the greatest common factor of 16 and 48 is 16.

That is

16x − 48 = 16(x−3)

Therefore, the greatest common factor of 16x − 48 is 16.

How To Solve Chapter 6 Factoring Out A Common Factor Key To Algebra Book 4

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor Page 13 Exercise 2 Answer

Question: Find the greatest common factor in the expression 30x + 45?

Solution:

Given the polynomial

30x + 45

Here it is asked to find the greatest common factor.

We know that the factors of 30 are

30 = 1,​2,​3,​5,​6,​10,​15,​30

And we know that the factors of 45 are

45 = 1,​3,​5,​9,​15,​45

So here there are 4 common factors for 30 and 45.

That is

1,3,5,15

Hence the greatest common factor of 30 and 45 is 15.

That is

30x + 45 = 15(2x+3)

Therefore, the greatest common factor of 30x + 45 is 15.

Page 13 Exercise 4 Answer

Question: Find the greatest common factor in the expression 200x + 80y − 120z?

Solution:

Given the polynomial

200x + 80y − 120z

Here it is asked to find the greatest common factor.

We know that the factors of 200 are

200 = 1,​2,​4,​5,​8,​10,​20,​25,​40,​50,​100,​200

The factors of 80 are

80 = 1,​2,​4,​5,​8,​10,​16,​20,​40,​80

The factors of 120 are

120 = 1,​2,​3,​4,​5,​6,​8,​10,​12,​15,​20,​24,​30,​40,​60,​120

So here there are 8 common factors for 200,80,120.

That is

1,2,4,5,8,10,20,40

Hence the greatest common factor of 200,80 and 120 is 40.

That is

200x + 80y − 120z = 40(5x+2y−3z)

Therefore, the greatest common factor of 200x + 80y − 120z is 40.

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor Page 13 Exercise 5 Answer

Question: Find the greatest common factor in the expression 72a − 96b − 48c?

Solution:

Given the polynomial

72a − 96b − 48c

Here it is asked to find the greatest common factor.

We know that the factors of 72 are

72 = 1,​2,​3,​4,​6,​8,​9,​12,​18,​24,​36,​72

The factors of 96 are

96 = 1,​2,​3,​4,​6,​8,​12,​16,​24,​32,​48,​96

The factors of 48 are

48 = 1,​2,​3,​4,​6,​8,​12,​16,​24,​48

So here there are 8 common factors for 72,96,48 are 1,2,3,4,6,8,12,24

Hence the greatest common factor of 72,96,48 is 24.

That is

72a − 96b − 48c = 24(3a−4b−2c)

Therefore, the greatest common factor of 72a − 96b − 48c is 24.

Page 13 Exercise 6 Answer

Question: Find the greatest common factor in the expression 32x2 + 40x + 160?

Solution:

Given the polynomial

32x2 + 40x + 160

Here it is asked to find the greatest common factor.

We know that the factors of 32 are

32 = 1,​2,​4,​8,​16,​32

The factors of 40 are

40 = 1,​2,​4,​5,​8,​10,​20,​40

The factors of 160 are

160 = 1,​2,​4,​5,​8,​10,​16,​20,​32,​40,​80,​160

So here there are 4 common factors for 32,40,160.

That is

1,2,4,8

Hence the greatest common factor of 32,40,160 is 8.

That is

32x2 + 40x + 160 = 8(4x2+5x+20)

Therefore, the greatest common factor of 32x2 + 40x + 160 is 8.

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor Page 13 Exercise 1 Answer

Question: Find the common factors in the polynomial x2 + 3x

Solution:

Given the polynomial

x2 + 3x

Here it is asked to find the common factor.

Here we can see that x is common to both terms.

That is

x2 + 3x = x(x+3)

Hence the common factor is x.

Therefore, the common factor is x.

Page 13 Exercise 2 Answer

Question: Find the common factors in the polynomial 5a2 + 2a

Solution:

Given the polynomial

5a2 + 2a

Here it is asked to find the common factor.

Here we can see that a is common to both terms.

That is

5a2 + 2a = a(5a+2)

Hence the common factor is a.

Therefore, the common factor is a.

Page 13 Exercise 3 Answer

Question: Find the common factors in the polynomial y2 − 7y

Solution:

Given the polynomial

y2 − 7y

Here it is asked to find the common factor.

Here we can see that y is common to both terms.

That is

y2 − 7y = y(y−7)

Hence the common factor is y.

Therefore, the common factor is y.

Page 13 Exercise 4 Answer

Question: Find the common factors in the polynomial 12x − x2

Solution:

Given the polynomial

12x − x2

Here it is asked to find the common factor.

Here we can see that x is common to both terms.

That is

12x − x2 = x(12−x)

Hence the common factor is x.

Therefore, the common factor is x.

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor Page 13 Exercise 5 Answer

Question: Find the common factors in the polynomial 3x3 + 2x2

Solution:

Given the polynomial

3x3 + 2x2

Here it is asked to find the common factor.

Here we can see that x2 is common to both terms.

That is

3x3 + 2x2 = x2(3x+2)

Hence the common factor is x2.

Therefore, the common factor is x2.

Page 13 Exercise 6 Answer

Question: Find the common factors in the polynomial x4 − 5x2

Solution:

Given the polynomial

x4 − 5x2

Here it is asked to find the common factor.

Here we can see that x2 is common to both terms.

That is

x4 − 5x2 = x2(x2−5)

Hence the common factor is x2.

Therefore, the common factor is x2.

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor Page 13 Exercise 7 Answer

Question: Find the common factors in the polynomial a3 + 5a2 + 3a

Solution:

Given the polynomial

a3 + 5a2 + 3a

Here it is asked to find the common factor.

Here we can see that a is common to both terms.

That is

a3 + 5a2 + 3a = a(a2+5a+3)

Hence the common factor is a.

Therefore, the common factor is a.

Page 8 Exercise 13 Answer

Question: Find the common factors in the polynomial 2x3 + x2 − 8x

Solution:

Given the polynomial

2x3 + x2 − 8x

Here it is asked to find the common factor.

Here we can see that x is common to both terms.

That is

2x3 + x2 − 8x = x(2x2+x−8)

Hence the common factor is x.

Therefore, the common factor is x.

Page 13 Exercise 9 Answer

Question: Find the common factors in the polynomial ab + 2b + b2

Solution:

Given the polynomial

ab + 2b + b2

Here it is asked to find the common factor.

Here we can see that b is common to both terms.

That is

ab + 2b + b2 = b(a+2+b)

Hence the common factor is b.

Therefore, the common factor is b.

Page 13 Exercise 10 Answer

Question: Find The Common Factor in The Polynomial 5x2y + xy + 7y

Solution:

Given the polynomial

5x2y + xy + 7y

Here it is asked to find the common factor.

Here we can see that y is common to both terms.

That is

5x2y + xy + 7y = y(5x2+x+7)

Hence the common factor is y.

Therefore, the common factor is y.

Mcgraw Hill Key To Algebra Chapter 6 Problem Walkthrough

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common FactorPage 13 Exercise 11 Answer

Question: Find The Common Factor In The Polynomial x3 − 4x2 + x

Solution:

Given the polynomial

x3 − 4x2 + x

Here it is asked to find the common factor.

Here we can see that x is common to both terms.

That is

x3 − 4x2 + x = x(x2−4x+1)

Hence the common factor is x.

Therefore, the common factor is x.

Page 13 Exercise 12 Answer

Question: Find The Common Factor In The Polynomial ab + b2 + 2bc

Solution:

Given the polynomial

ab + b2 + 2bc

Here it is asked to find the common factor.

Here we can see that b is common to both terms.

That is

ab + b2 + 2bc = b(a+b+2c)

Hence the common factor is b.

Therefore, the common factor is b.

Page 14 Exercise 1 Answer

Question: Find The Common Factor In The Polynomial 5x2 + 10x

Solution:

Given the polynomial

5x2 + 10x

Here it is asked to find the common factor.

Here we can see that 5x is common to both terms.

That is

5x2 + 10x = 5x(x+2)

Hence the common factor is 5x.

Therefore, the common factor is 5x and can be written as 5x(x+2).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor Page 14 Exercise 2 Answer

Question: Find The Common Factor In The Polynomial 8a2 − 2a

Solution:

Given the polynomial

8a2 − 2a

Here it is asked to find the common factor.

Here we can see that 2a is common to both terms.

That is

8a2 − 2a = 2a(4a−1)

Hence the common factor is 2a.

Therefore, the common factor is 2a and can be written as 2a(4a−1).

Page 14 Exercise 3 Answer

Question: Find The Common Factor In The Polynomial 4y5 + 3y3

Solution:

Given the polynomial

4y5 + 3y3

Here it is asked to find the common factor.

Here we can see that y3 is common to both terms.

That is

4y5 + 3y3 = y3(4y2+3)

Hence the common factor is y3.

Therefore, the common factor is y3 and can be written as y3(4y2+3).

Page 14 Exercise 4 Answer

Question: Find The Common Factor In The Polynomial x2y2 + x3y

Solution:

Given the polynomial

x2y2 + x3y

Here it is asked to find the common factor.

Here we can see that x2y is common to both terms.

That is

x2y2 + x3y = x2y(y+x)

Hence the common factor is x2y.

Therefore, the common factor is x2y and can be written as x2y(y+x).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor Page 14 Exercise 5 Answer

Question: Find The Common Factor In The Polynomial x2y2 + xy

Solution:

Given the polynomial

x2y2 + xy

Here it is asked to find the common factor.

Here we can see that xy is common to both terms.

That is

x2y2 + xy = xy(xy+1)

Hence the common factor is xy.

Therefore, the common factor is xy and can be written as xy(xy+1).

Page 14 Exercise 6 Answer

Question: Find The Common Factor In The Polynomial 3x + 12x2

Solution:

Given the polynomial

3x + 12x2

Here it is asked to find the common factor.

Here we can see that 3x is common to both terms.

That is

3x + 12x2 = 3x(1+4x)

Hence the common factor is 3x.

Therefore, the common factor is 3x and can be written as 3x(1+4x).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor Page 14 Exercise 7 Answer

Question: Find The Common Factor In The Polynomial 6x3 − 9x2

Solution:

Given the polynomial

6x3 − 9x2

Here it is asked to find the common factor.

Here we can see that 3x2 is common to both terms.

That is

6x3 − 9x2 = 3x2(2x−3)

Hence the common factor is 3x2.

Therefore, the common factor is 3x2 and can be written as 3x2(2x−3).

Page 14 Exercise 8 Answer

Question: Find The Common Factor In The Polynomial 4x2 + 6xy

Solution:

Given the polynomial

4x2 + 6xy

Here it is asked to find the common factor.

Here we can see that 2x is common to both terms.

That is

4x2 + 6xy = 2x(2x+3y)

Hence the common factor is 2x.

Therefore, the common factor is 2x and can be written as 2x(2x+3y).

Page 14 Exercise 10 Answer

Question: Find The Common Factor In The Polynomial 12a2 − 18ab

Solution:

Given the polynomial

12a2 − 18ab

Here it is asked to find the common factor.

Here we can see that 3a is common to both terms.

That is

12a2 − 18ab = 3a(4a−6b)

Hence the common factor is 3a.

Therefore, the common factor is 3a and can be written as 3a(4a−6b).

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor Page 14 Exercise 11 Answer

Question: Factorize the polynomial -7x3 − 7x2

Solution:

Given: Polynomial -7x3 − 7x2

To find: A factorized form of a given polynomial.

Factorize each of the terms in the given polynomial expression

⇒ 7 × x × x × x − 7 × x × x

As both of the terms have 7 × x × x common. So, from distributive law relation, we can rewrite it as

⇒ 7 × x × x(x−1)

⇒ 7x2(x−1)

Hence, the final factorized form of the given polynomial is 7x2(x−1)

Page 14 Exercise 12 Answer

Question: Factorize the polynomial -25x + 30xy

Solution:

Given: Polynomial -25x + 30xy

To find: A factorized form of a given polynomial.

Factorize each of the terms in the given polynomial expression

⇒ 5 × 5 × x + 2 × 3 × 5 × x × y

As both of the terms have a common 5 × x. So, from distributive law relation, we can rewrite it as

⇒ 5 × x(5+2×3×y)

⇒ 5x(5+6y)

Hence, the final factorized form of the given polynomial is 5x(5+6y)

Worked Examples For Chapter 6 Factoring Out A Common Factor Mcgraw Hill

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor Page 14 Exercise 13 Answer

Question: Factorize the polynomial -x6 + x5 − x4

Solution:

Given: Polynomial -x6 + x5 − x4

To find: A factorized form of a given polynomial.

Factorize each of the terms in the given polynomial expression

⇒ x × x × x × x × x × x + x × x × x × x × x − x × x × x × x

As both of the terms have common x × x × x × x. So, from distributive law relation, we can rewrite it as

⇒ x × x × x × x(x×x+x−1)

⇒ x4(x2+x−1)

Hence, the final factorized form of the given polynomial is x4(x2+x−1)

Page 14 Exercise 15 Answer

Question: Factorize the polynomial -5a3 + 3a4 + 6a3

Solution:

Given: Polynomial -5a3 + 3a4 + 6a3

To find: A factorized form of a given polynomial.

Two of the terms have variable with the same power, so the like terms will get added directly,

⇒ 11a3 + 3a4

Factorise each of the terms in the given polynomial expression

⇒ 11 × a × a × a + 3 × a × a × a × a

As, both of the terms have common a × a × a. So, from distributive law relation we can rewrite it as

⇒ a × a × a(11+3×a)

⇒ a3(11+3a)

Hence, the final factorized form of the given polynomial is a3(11+3a)

Page 14 Exercise 16 Answer

Question: Factorize the polynomial -6x2y − xy2 + 2x2y2

Solution:

Given: Polynomial -6x2y − xy2 + 2x2y2

To find: A factorized form of a given polynomial.

Factorise each of the terms in the given polynomial expression

⇒ 2 × 3 × x × x × y − x × y× y + 2 × x × x × y × y

As both of the terms have common x × y. So, from distributive law relation, we can rewrite it as

⇒ x × y(2×3×x−y+2×x×y)

⇒ xy(6x−y+2xy)

Hence, the final factorized form of the given polynomial is xy(6x−y+2xy)

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor Page 14 Exercise 17 Answer

Question: Factorize the polynomial -x3y + x2y + x2y2

Given: Polynomial -x3y + x2y + x2y2

To find: A factorized form of a given polynomial.

Factorise each of the terms in the given polynomial expression

⇒ x × x × x × y + x × x × y + x × x × y × y

As both of the terms have common x × x × y. So, from distributive law relation, we can rewrite it as

⇒ x × x × y(x+1+y)

⇒ x2y(x+y+1)

Hence, the final factorized form of the given polynomial is x2y(x+y+1)

Page 14 Exercise 18 Answer

Question: Factorize the polynomial -a3b3 + a2b2 + ab

Solution:

Given: Polynomial -a3b3 + a2b2 + ab

To find: A factorized form of a given polynomial.

Factorise each of the terms in the given polynomial expression

⇒ a × a × a × b × b × b + a × a × b × b + a × b

As both of the terms have common a × b. So, from distributive law relation, we can rewrite it as

⇒ a × b(a×a×b×b+a×b+1)

⇒ ab(a2b2+ab+1)

Hence, the final factorized form of the given polynomial is ab(a2b2+ab+1)

Page 14 Exercise 19 Answer

Question: Factorize the polynomial -12a3 − 9a2 − 6a

Solution:

Given: Polynomial -12a3 − 9a2 − 6a

To find: A factorized form of a given polynomial.

Factorise each of the terms in the given polynomial expression

⇒ 2 × 2 × 3 × a × a × a − 3 × 3 × a × a − 2 × 3 × a

As, both of the terms have a common 3 × a. So, from distributive law relation we can rewrite it as

⇒ 3 × a(2×2×a×a−3×a−2)

⇒ 3a(4a2−3a−2)

Hence, the final factorized form of the given polynomial is 3a(4a2−3a−2)

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 6 Factoring Out A Common Factor Page 14 Exercise 23 Answer

Question: Factorize the biggest term in the polynomial 63x4 + 81x3 − 72x2?

Solution:

Given the polynomial to factorize: 63x4 + 81x3 − 72x2

Now:

We have to factorize this polynomial by factoring out the biggest terms out of the polynomial.

63x4 + 81x3 − 72x2

63x4 + 81x3 − 72x2=9x2(7x2+9x-8)

Now see that:

⇒ \(\begin{aligned}
& \frac{63 x^4}{9 x^2}=7 x^2 \\
& \frac{81 x^3}{9 x^2}=9 x \\
& \frac{72 x^2}{9 x^2}=8
\end{aligned}\)

Here 9x² is the biggest single term that can be taken out as a factor as it is the greatest term that is a factor of 63x4,81x3,72x2

The polynomial after factoring out the biggest term is as follows: 63x4 + 81x3 − 72x2 = 9x2(7x2+9x−8)

Page 14 Exercise 24 Answer

Question: Factorize the biggest term in the polynomial 60a2 + 30ab − 90ac?

Solution:

Given the polynomial to factorize: 60a2 + 30ab − 90ac

Now:

We have to factorize this polynomial by factoring out the biggest terms out of the polynomial.

60a2+30ab-90ac

60a2+30ab-90ac=30a(2a+b-3c)

Now see that:

⇒ \(\begin{aligned}
\frac{60 a^2}{30 a} & =2 a \\
\frac{30 a b}{30 a} & =b \\
\frac{90 a c}{30 a} & =3 c
\end{aligned}\)

Here 30a is the biggest single term that can be taken out as a factor as it is the greatest term that is a factor of 60a², 30ab,90ac

The polynomial after factoring out the biggest term is as follows: 60a2 + 30ab − 90ac = 30a(2a+b−3c)

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 5 The Distributive Principle

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 5 The Distributive Principle

Page 8 Exercise 1 Answer

Question: Solve The Polynomial 3(2x−5) By Using Distributive Principle?

Solution:

Given Polynomial: 3(2x−5)

Let us solve the equation using the distributive Principle.

⇒ 3(2x-5)

∴  3(2x-5)=3x2x-3×5 ( Using distributive principle )

∴ 3x2x-3×5=6x-15

3(2x−5) ⇒ 6x − 15

Mcgraw Hill Distributive Principle Solutions Chapter 5 Key To Algebra

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 5 The Distributive Principle Page 8 Exercise 3 Answer

Question: Solve The Polynomial 2 (3a+4b) By Using Distributive Principle?

Solution:

Given Equation:

⇒ 2 (3a+4b)

To find: Simplify using the distributive principle.

Let us solve the equation using the distributive Principle.

⇒ 2(3a+4b)

∴2 (3a+4b)=2x3a+2x4b

⇒ 6a+8b

2(3a+4b) ⇒ 6a+8b

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 5 The Distributive Principle

Page 8 Exercise 5 Answer

Question: Solve The Polynomial 4(3x−y+5) By Using Distributive Principle?

Given:

⇒ 4(3x−y+5)

To find:

Simplify using the distributive principle.

Let us solve the equation using the distributive Principle.

⇒ 4(3x-y+5) (use distributive principle)

∴ (4x3x)-(4xy)+(4×5)

⇒ 12x-4y+20

Using distributive Principle.

4(3x−y+5) ⇒ 12x − 4y + 20

Page 8 Exercise 7 Answer

Question: Solve The Polynomial 6(3x−y+5) By Using Distributive Principle?

Solution:

Given:

⇒ 6(3x−y+5)

To find:

Simplify using the distributive principle

Let us solve the equation using the distributive Principle.

⇒ 6(3x-y+5) use distributive principle

∴ 6x3x-6xy+6×5

⇒ 18x-6y+30 ( Using distributive Principle)

6(3x−y+5) ⇒ 18x − 6y + 30

Chapter 5 The Distributive Principle Mcgraw Hill Algebra Key

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 5 The Distributive Principle Page 8 Exercise 1 Answer

Question: Solve The Polynomial −5(2x−4) By Using Distributive Principle?

Solution:

Given:

⇒ −5(2x−4)

To find:

Simplify using the distributive principle

Let us solve the equation using the distributive Principle.

⇒ -5(2x-4) (Use distributive principle)

∴ -5(2x-4) ⇒-5x2x-(-5)x4

⇒ -5(2x-4)⇒-10x+20

−5(2x−4) ⇒ −10x + 20

Page 8 Exercise 2 Answer

Question: Solve The Polynomial −4(3y+5) By Using Distributive Principle?

Solution:

Given:

⇒ −4(3y+5)

To find: Simplify using the distributive principle

Let us solve the equation using the distributive Principle.

⇒ -4(3y+5)

∴ -4(3y+5)⇒-4x3y+(-4)x5

⇒ -4(3y+5)⇒-12y-20

−4(3y+5) ⇒ −12y − 20

Page 8 Exercise 4 Answer

Question: Solve The Polynomial (a+x)−8 By Using Distributive Principle?

Solution:

Given:

⇒ (a+x)−8

To find:

Simplify using the distributive principle

Let us solve the equation using the distributive Principle.

⇒ (a+x)-8 (use distributive principle)

∴ (a+x)-8⇒ 1xa+1×x-8

∴ (a+x)-8⇒a+x-8

(a+x)−8 ⇒ a + x − 8

How To Solve Chapter 5 The Distributive Principle Key To Algebra Book 4

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 5 The Distributive Principle Page 8 Exercise 5 Answer

Question: Solve The Polynomial −4(3x2−6x+2) By Using Distributive Principle?

Solution:

Given:

⇒ −4(3x2−6x+2)

To find:

Simplify using the distributive principle

Let us solve the equation using the distributive Principle.

The given equation is:

⇒ -4(3×2-6x+2) (use distributive principle)

∴ -4(3×2-6x+2)

∴ \(-4\left(3 x^2-6 x+2\right)=-4 \times 3 x^2+4 \times 6 x-4 \times 2\)

∴\(-4\left(3 x^2-6 x+2\right)=-12 x^2+24 x-8\)

−4(3x2−6x+2) ⇒ −12x2 + 24x − 8

Page 8 Exercise 7 Answer

Question: Solve The Polynomial −1(3x2−6x+2) By Using Distributive Principle?

Solution:

Given: −1(3x2−6x+2)

To find: We have to use the distributive principle to multiply.

We can write

−1(3x2−6x+2) = −(3x2−6x+2)

Further solving using the distributive principle we get

−1(3x2−6x+2) = −3x2 + 6x − 2

Hence using the Distributive principle to solve −1(3x2−6x+2) we get −3x2 + 6x − 2.

Page 8 Exercise 8 Answer

Question: Solve The Polynomial (3x2+6x−2)(−10) By Using Distributive Principle?

Solution:

Given: (3x2+6x−2)(−10)

To find: We have to use the distributive principle to multiply.

We can write

(3x2−60x+20)(−10) = −(30x2−60x+20)

Further solving using the Distributive principle we get

(3x2−60x+20)(−10) = −30x2 + 60x − 20

Hence using Distributive principle to solve (3x2−60x+20)(−10) we get −30x2 + 60x − 20

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 5 The Distributive Principle Page 8 Exercise 1 Answer

Question: Solve The Polynomial (2x−7)x By Using Distributive Principle?

Solution:

Given: (2x−7)x

To find: We have to use the distributive principle to multiply.

According to the Distributive principle, we just have to multiply the single term times each term in the polynomial

We get

(2x−7)x = 2x2 − 7x

Hence using the Distributive principle to solve(2x−7)x we get 2x2 − 7x.

Question: Solve The Polynomial (3y+5)y By Using Distributive Principle?

Solution:

Page 8 Exercise 2 Answer

Given: (3y+5)y

To find: We have to use the distributive principle to multiply.

According to Distributive principle, we just have to multiply the single term times each term in the polynomial

We get

(3y+5)y = 3y2 + 5y

Hence using Distributive principle to solve (3y+5)y we get 3y2 + 5y

Question: Solve The Polynomial 2 (3a+4b) By Using Distributive Principle?

Solution:

Page 8 Exercise 3 Answer

Given: 2 (3a+4b)

To find: We have to use the distributive principle to multiply.

According to the Distributive principle we just have to multiply the single term times each term in the polynomial

We get

x(5−8y) = 5x − 8xy

Hence using the Distributive principle to solve x(5−8y) we get 5x − 8xy.

Question: Solve The Polynomial x(2y2+3x−4) By Using Distributive Principle?

Solution:

Page 8 Exercise 6 Answer

Given: x(2y2+3x−4)

To find: We have to use distributive principle to do the multiplication.

According to Distributive principle, we just have to multiply the single term times each term in the polynomial

We get

x(2y2+3x−4) = 2xy2 + 3x2 − 4x

Hence using Distributive principle to solve x(2y2+3x−4) we get 2xy2 + 3x2 − 4x

Mcgraw Hill Algebra Book 4 Chapter 5 Explanations

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 5 The Distributive Principle Page 8 Exercise 7 Answer

Question: Solve The Polynomial (2y2+3x−4)xy By Using Distributive Principle?

Solution:

Given:(2y2+3x−4)xy

To find: We have to use distributive principle to do the multiplication.

According to the Distributive principle, we just have to multiply the single term times each term in the polynomial

We get

(2y2+3x−4)xy = 2xy3 + 3x2y − 4xy

Hence using the Distributive principle to solve (2y2+3x−4)xy we get 2xy3 + 3x2y − 4xy.

Page 8 Exercise 1 Answer

Question: Solve The Polynomial 5x(4x−7)By Using Distributive Principle?

Solution:

Given: 5x(4x−7)

To find: We have to use distributive principle to do the multiplication.

According to the Distributive principle, we just have to multiply the single term times each term in the polynomial

We get

5x(4x−7) = 20x2 − 35x

Hence using Distributive principle to solve 5x(4x−7) we get 20x2 − 35x

Page 8 Exercise 2 Answer

Question: Solve The Polynomial 3a(4a+2) By Using Distributive Principle?

Solution:

Given: 3a(4a+2)

To find: We have to use distributive principle to do the multiplication.

According to the Distributive principle we just have to multiply the single term times each term in the polynomial, We get,

3a(4a+2) = 12a2 + 6a

Hence using the Distributive principle to solve 3a(4a+2) we get 12a2 + 6a.

Page 8 Exercise 3 Answer

Question: Solve The Polynomial 4x(x2−5)By Using Distributive Principle?

Solution:

Given: 4x(x2−5)

To find: We have to use distributive principle to do the multiplication.

According to the Distributive principle, we just have to multiply the single term times each term in the polynomial

We get

4x(x2−5) = 4x3 − 20x

Hence using Distributive principle to solve 4x(x2−5) we get 4x3 − 20x

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 5 The Distributive Principle Page 8 Exercise 4 Answer

Question: Solve The Polynomial (2x+1)2x2 By Using Distributive Principle?

Solution:

Given: (2x+1)2x2

To find: We have to use distributive principle to do the multiplication.

According to the Distributive principle we just have to multiply the single term times each term in the polynomial

We get(2x+1)2x2 = 4x3 + 2x2

Hence using the Distributive principle to solve (2x+1)2x2 we get 4x3 + 2x2.

Page 8 Exercise 5 Answer

Question: Solve The Polynomial (3y−6)(−5y) By Using Distributive Principle?

Solution:

Given:(3y−6)(−5y)

To find: We have to use the distributive principle to multiply.

According to the Distributive principle, we just have to multiply the single term times each term in the polynomial

We get (3y−6)(−5y) = −15y2 + 30y

Hence using Distributive principle to solve (3y−6)(−5y) we get −15y2 + 30y

Page 8 Exercise 6 Answer

Question: Solve The Polynomial 7x(3x+4y) By Using Distributive Principle?

Solution:

We are given the expression 7x(3x+4y).

The objective is to use the Distributive Principle for a multiplication problem.

Given: 7x(3x+4y)
on Applying the distribution Principle, we get

7x(3x+4y)=7x.3x+7x.4y
=21x²+28xy

Hence, using the Distributive principle for the given multiplication problem 7x(3x+4y), we get the result 21x2 + 28xy.

Page 8 Exercise 7 Answer

Question: Solve The Polynomial 3a(4a−2b+c) By Using Distributive Principle?

Solution:

We are given the expression 3a(4a−2b+c).

The objective is to use the Distributive Principle for a multiplication problem.

Given: 3a(4a-2b+c)
On applying the distributive principle
3a(4a-2b+c)=3a.4a-3a.2b+3a.c
3a(4a-2b+c)=12a²-6ab+3ac

Hence, using the Distributive principle for the given multiplication problem 3a(4a−2b+c), we get the result 12a2 − 6ab + 3ac.

Page 8 Exercise 8 Answer

Question: Solve The Polynomial 5y(3x+4y−8) By Using Distributive Principle?

Solution:

We are given the expression 5y(3x+4y−8).

The objective is to use the Distributive Principle for a multiplication problem.

Given: 5y(3x+4y-8)

On applying the distributive principle, we get

5y(3x+4y-8)=5y.3x+5y.4y-5y.8
=15xy+20y²-40y

Hence, using the Distributive principle for the given multiplication problem 5y(3x+4y−8), we get the result 15xy + 20y2 − 40y.

Mcgraw Hill Key To Algebra Chapter 5 Problem Walkthrough

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 5 The Distributive Principle Page 8 Exercise 9 Answer

Question: Solve The Polynomial 2xy(3x+4y−8). By Using Distributive Principle?

Solution:

We are given the expression 2xy(3x+4y−8).

The objective is to use the Distributive Principle for a multiplication problem.

Given: 2xy(3x+4y-8)

on applying the distributive principle, we get

2xy(3x+4y-8)=2xy.3x+2xy.4y-32xy.8
=6x2y+8xy2-16xy

Hence, using the Distributive principle for the given multiplication problem 2xy(3x+4y−8), we get the result 6x2y + 8xy2 − 16xy.

Page 8 Exercise 10 Answer

Question: Solve The Polynomial 7x2−5x−6)6x2 By Using Distributive Principle?

Solution:

We are given the expression 7x2−5x−6)6x2.

The objective is to use the Distributive Principle for a multiplication problem.

Hence, using the Distributive principle for the given multiplication problem (7×2−5x−6)6×2, we get the result 42x4 − 30x3 − 36x2.

Page 8 Exercise 11 Answer

Question: Solve The Polynomial −4b(a−3b+c) By Using Distributive Principle?

Solution:

We are given the expression −4b(a−3b+c).

The objective is to use the Distributive Principle for a multiplication problem.

Given: 2xy(3x+4y-8)
on applying the distributive principle, we get

2xy(3x+4y-8)=2xy.3x+2xy.4y-2xy.8
=6x²y+8xy²-16xy

Hence, using the Distributive principle for the given multiplication problem −4b(a−3b+c), we get the result −4ab + 12b2 − 4bc.

Page 8 Exercise 12 Answer

Question: Solve The Polynomial 7x2y(3x2y+2xy2+x3) By Using Distributive Principle?

Solution:

We are given the expression 7x2y(3x2y+2xy2+x3).

The objective is to use the Distributive Principle for a multiplication problem.

Given: 7x²y(3x²y+2xy²+x3)

on applying the distributive principle, we get

7x²y(3x²y+2xy²+x³)=7x²y.3x²y+7x²y.2xy²+7x²y.x³
=21x4y²+14x³y³+14x³y³+7x5y

Hence, using the Distributive principle for the given multiplication problem 7x2y(3x2y+2xy2+x3), we get the result 21x4y2 + 14x3y3 + 7x5y.

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 5 The Distributive Principle Page 9 Exercise 1 Answer

Question: Solve The Equation 5(x+3) = 35. And Find The Value of x?

Solution:

We are given the equation 5(x+3) = 35.

The objective is to solve the given equation.

Given: 5(x+3)=35 on applying distributive principle, we get

5x+5.3=35
5x+15=35
5×35-15
5x=20
x= \(\frac{20}{5}\)
x=4

Hence, the solution of the given equation 5(x+3) = 35 is x = 4.

Page 9 Exercise 3 Answer

Question: Solve The Equation 2(3x+15) = 18. And Find The Value of x?

Solution:

We are given the equation 2(3x+15) = 18.

The objective is to solve the given equation.

Given: 2(3x+15)=18
on applying the distributive principle, we get

2.3x+2.15=18
6x+30=18
6x=18-30
6x=-12
\(x=\frac{-12}{6}\)
x-2

Hence, the solution of the given equation 2(3x+15) = 18 is x = −2.

Page 9 Exercise 4 Answer

Question: Find The Value Of x In The Expression 8(x−2) = 32.

Solution:

We are given the equation 8(x−2) = 32.

The objective is to solve the given equation.

Given: 8(x-2)=32
By applying the distributive principle, we get
5x+5.3=35
5x+15=35
5x=35-15
5x=20
x= \(\frac{20}{5}\)
x=4

Hence, the solution of the given equation 8(x−2) = 32 is x = 6.

Page 9 Exercise 5 Answer

Question: Find The Value Of a In The Expression 5(a+3) = 8a.?

Solution:

We are given the equation 5(a+3) = 8a.

The objective is to solve the given equation.

Let Us Assume That a= x

2(3x+15)=18 on applying distributive principle, we get

2.3x+2.15=18

6x+30=18

6x=18-30

6x=-12

x= \(\frac{-12}{6}\)

x=-2

Hence, the solution of the given equation 5(a+3) = 8a is a = 5.

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 5 The Distributive Principle Page 9 Exercise 6 Answer

Question: Find The Value Of x In The Expression 7x = 4(x+6)?

Solution:

We are given the equation 7x = 4(x+6).

The objective is to solve the given equation.

Given: 7x=4(x+6)

On applying the distributive principle, we get

7x=4.x+4.6

7x=4x+24

7x-4x=24

3x=24

\(x=\frac{24}{3}\)

x=8

Hence, the solution of the given equation 7x = 4(x+6) is x = 8.

Page 9 Exercise 7 Answer

Question: Find The Value Of x In The Expression 4(x+5) = 3(x−6)?

Solution:

We are given the equation 4(x+5) = 3(x−6).

The objective is to solve the given equation.

Given: 4(x+5)=3(x-6)

on applying the distributive principle, we get

4x+4.5=3.-3.6

4x+20=3x-18

4x-3x=-18-20

x=-38

Hence, the solution of the given equation 4(x+5) = 3(x−6) is x = −38.

Page 9 Exercise 8 Answer

Question: Find The Value Of x In The Expression 3(2x−5)+4 = 31?

Solution:

We are given the equation 3(2x−5)+4 = 31.

The objective is to solve the given equation.

3(2x-5)+4=31 on applying the distributive principle, we get

3.2x-3.5+4=31

6x-15=31

6x-11=31

6x=31+11

6x=42

x= \(\frac{42}{6}\)

x=7

Hence, the solution of the given equation 3(2x−5) + 4 = 31 is x = 7.

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 5 The Distributive Principle Page 9 Exercise 9 Answer

Question: Find The Value Of x In The Expression 10 = 18 + 4(3x+7)?

Solution:

We are given the equation 10 = 18 + 4(3x+7).

The objective is to solve the given equation.

10=18+4(3x+7) on applying distributive principle, we get

10=18+4.3x+4.7

10=18+12x+28

10=12x+46

10-46=12x

-36=12x

x= \(\frac{-36}{12}\)

Hence, the solution of the given equation 10 = 18 + 4(3x+7) is x = −3.

Page 9 Exercise 10 Answer

Question: Find The Value Of x In The Expression 3(3x+5) = 2(6x−3)?

Solution:

Given expression is 3(3x+5) = 2(6x−3)

We find the solution for a given expression

We use the distributive principle for a given expression

Given: 3(3x+5)=2(6x-3) ( we use the distributive principle)

3.3x+3.5=2.6x-3.2

9x+15=12x-6

12x-9x=15+6

3x=21

x=\(\frac{21}{3}\)

x=7

The solution for the given polynomial is x = 7.

Page 10 Exercise 1 Answer

Question: Find The Area Of The Rectangle Whose Length  = 3x and Breadth = 2x + 5?

Solution:

Given the length of the rectangle = 3x

Breadth of rectangle = 2x + 5

We find the polynomial for the area of the given rectangle

We write the formula for area of the rectangle,

A=lxb

A=3x(2x+5)

we use distributive principle

A=6x²+15x

The polynomial for the area of a given rectangle is A = 6x2 + 15x

Worked Examples For Chapter 5 The Distributive Principle Mcgraw Hill

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 5 The Distributive Principle Page 10 Exercise 2 Answer

Question: Find The Area Of The Rectangle Whose Length  = 3x + 4 and Breadth = 2?

Solution:

Given : Length of rectangle = 3x + 4

Breadth of rectangle = 2

We find a polynomial for the area of the given rectangle

We write the formula for the area of a rectangle,
Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 5 Distributive Principle Page 10 Exercise 2 Answer

Polynomial for area of given rectangle is A = 6x + 8

Page 10 Exercise 4 Answer

Question: Find The Area Of The Rectangle Whose Length  = 2r + 7 and Breadth = p?

Solution:

Given: Length of rectangle = 2r + 7

Breadth of rectangle = p

We find the polynomial for area of given rectangle

We write formula for area of rectangle,
Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 5 Distributive Principle Page 10 Exercise 4 Answer

The polynomial for area of given rectangle is 2rp + 7p

Page 10 Exercise 6 Answer

Question: Find The Area Of The Rectangle Whose Length  = 7n + 4 and Breadth = 5n?

Solution:

Given: Length of rectangle = 7n + 4

Breadth of rectangle = 5n

We find the polynomial for area of given rectangle

We write the formula for area of rectangle,

A=lxb

a=(7n+4)x(5n)

a= 35n2 + 20n (we use distributive principle)

The polynomial for area of a given rectangle is A = 35n2 + 20n

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 4 Subtracting Polynomials

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 4 Subtracting Polynomials

Page 4 Exercise 1 Answer

Question: Subtract The Polynomials (3x2+5x−2) and (7x2−5x+4)

Solution: 

Given Polynomials:

(3x2+5x−2) and (7x2−5x+4)

To find: The subtraction of polynomials

3x²-8x+2

(3x²-8x+2)×(-1).3x²-(-1).8x+(-1).2

(3x²-8x+2)×(-1)=-3x²+8x-2-4

(3x²+5x-2)-(7x²-5x+4)= 3x²-7x²+5x-2-4

(3x²+5x-2)-(7x²-5x+4)=-4x²+10x-6

The subtraction of polynomials: (3x2+5x−2) − (7x2−5x+4) = −4x2 + 10x − 6

Mcgraw Hill Key To Algebra Book 4 Chapter 4 Solutions

Page 4 Exercise 2 Answer

Question: Subtract The Polynomials (6x2+2x−2) and (x2+4x−1)

Solution: 

Given Polynomials:

(6x2+2x−2) and (x2+4x−1)

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 4 Subtracting Polynomials

To find: The subtraction of polynomials

(6x²+2x-2)-(x²+4x-1)

(6x²+2x-2)-(x²+4x-1)=6x²+2x-2-x²4x+1

(6x²+2x-2)-(x²+4x-1)=6x²-x²+2x-4x-2+1

(6x²+2x-2)-(x²+4x-1)=5x²-2x-1

The subtraction of polynomials: (6x2+2x−2) − (x2+4x−1) = 5x2 − 2x − 1

Page 4 Exercise 3 Answer

Question: Subtract The Polynomials (2y2−y+3) and (3y2−y−4)

Solution: 

Given Polynomials:

(2y2−y+3) and (3y2−y−4)

To find: The subtraction of polynomials

(2y²-y+3)-(3y²-y-4)

(2y²-y+3)-(3y²-y-4)=2y²-y+3y²+y+4

(2y²-y+3)-(3y²-y-4)=2y²-3y²-y+y+3+4

(2y²-y+3)-(3y²-y-4)=-y²+7

The subtraction of polynomials: (2y2−y+3) − (3y2−y−4) = −y2 + 7

Page 4 Exercise 4 Answer

Question: Subtract The Polynomial (y2+y−6) and (y2+5y−6)

Solution: 

Given Polynomials:

(y2+y−6) and (y2+5y−6)

To find: The subtraction of polynomials

\(\begin{aligned}
& \left(y^2+y-6\right)-\left(y^2+5 y-6\right) \\
& \left(y^2+y-6\right)-\left(y^2+5 y-6\right)=y^2+y-6-y^2-5 y+6 \\
& \left(y^2-y-6\right)-\left(y^2+5 y-6\right)=y^2-y^2+y-5 y-6+6 \\
& \left(y^2-y-6\right)-\left(y^2+5 y-6\right)=-4 y
\end{aligned}\)

The subtraction of polynomials: (y2+y−6) − (y2+5y−6) = −4y

Key To Algebra Book 4 Subtracting Polynomials Chapter 4 Answers

Page 4 Exercise 5 Answer

Question: Subtract The Polynomials (4x2+3x+5) and (4x2−3x+5)

Solution: 

Given Polynomials:

(4x2+3x+5) − (4x2−3x+5)

To find: The subtraction of polynomials

\(\begin{aligned}
& \left(4 x^2+3 x+5\right)-\left(4 x^2-3 x+5\right) \\
& \left(4 x^2+3 x+5\right)-\left(4 x^2-3 x+5\right)=4 x^2+3 x+5-4 x^2+3 x-5 \\
& \left(4 x^2+3 x+5\right)-\left(4 x^2-3 x+5\right)=4 x^2-4 x^2+3 x+3 x+5-5 \\
& \left(4 x^2+3 x+5\right)-\left(4 x^2-3 x+5\right)=6 x
\end{aligned}\)

The subtraction of polynomials: (4x2+3x+5) − (4x2−3x+5) = 6x

Page 4 Exercise 6 Answer

Question: Subtract The Polynomials (3x2+5x−2) and (2x2−3x+7)

Solution: 

Given Polynomials:

(3x2+5x−2) and (2x2−3x+7)

To find: The subtraction of polynomials

\(\begin{aligned}
& \left(3 x^2+5 x-2\right)-\left(2 x^2-3 x+7\right) \\
& \left(3 x^2+5 x-2\right)-\left(2 x^2-3 x+7\right)=3 x^2+5 x-2-2 x^2+3 x-7 \\
& \left(3 x^2+5 x-2\right)-\left(2 x^2-3 x+7\right)=3 x^2-2 x^2+5 x+3 x-2-7 \\
& \left(3 x^2+5 x-2\right)-\left(2 x^2-3 x+7\right)=x^2+8 x-9
\end{aligned}\)

The subtraction of polynomials: (3x2+5x−2) − (2x2−3x+7) = x2 + 8x − 9

Page 4 Exercise 8 Answer

Question: Subtract The Polynomials (5a2−2a−8) and (a2−6a+3)

Solution: 

Given Polynomials: (5a2−2a−8) and (a2−6a+3)

To find: The subtraction of polynomials

\(\begin{aligned}
& \left(5 a^2-2 a-8\right)-\left(a^2-6 a+3\right) \\
& \left(5 a^2-2 a-8\right)-\left(a^2-6 a+3\right)=5 a^2-2 a-8-a^2+6 a-3 \\
& \left(5 a^2-2 a-8\right)-\left(a^2-6 a+3\right)=5 a^2-a^2-2 a+6 a-8-3 \\
& \left(5 a^2-2 a-8\right)-\left(a^2-6 a+3\right)=4 a^2+4 a-11
\end{aligned}[latex]

The subtraction of polynomials: (5a2−2a−8) − (a2−6a+3) = 4a2 + 4a − 11

Page 4 Exercise 9 Answer

Question: Subtract The Polynomials (8x2−8x−3) and (4x+2)

Solution: 

Given Polynomials:

(8x2−8x−3) and (4x+2)

To find: The subtraction of polynomials

⇒ [latex]\begin{aligned}
& \left(8 x^2-8 x-3\right)-(4 x+2) \\
& \left(8 x^2-8 x-3\right)-(4 x+2)=8 x^2-8 x-3-4 x-2 \\
& \left(8 x^2-8 x-3\right)-(4 x+2)=8 x^2-8 x-4 x-3-2 \\
& \left(8 x^2-8 x-3\right)-(4 x+2)=8 x^2-12 x-5
\end{aligned}\)

The subtraction of polynomials: (8x2−8x−3) − (4x+2) = 8x2 − 12x − 5

Mcgraw Hill Subtracting Polynomials Solutions Chapter 4 Key To Algebra

Page 4 Exercise 10 Answer

Question: Subtract The Polynomials (3x2+5x−1) and (4x2−2x+4)

Solution: 

Given Polynomials:

(3x2+5x−1) and (4x2−2x+4)

To find: The Subtraction of polynomials

\(\begin{aligned}
& \left(3 x^2+5 x-1\right)-\left(4 x^2-2 x+4\right) \\
& \left(3 x^2+5 x-1\right)-\left(4 x^2-2 x+4\right)=3 x^2+5 x-1-4 x^2+2 x-4 \\
& \left(3 x^2+5 x-1\right)-\left(4 x^2-2 x+4\right)=3 x^2-4 x^2+5 x+2 x-1-4 \\
& \left(3 x^2+5 x-1\right)-\left(4 x^2-2 x+4\right)=-x^2+7 x-5
\end{aligned}\)

The subtraction of polynomials: (3x2+5x−1) − (4x2−2x+4) = −x2 + 7x − 5

Page 5 Exercise 3 Answer

Question: Subtract The polynomials (3x2+5x−2) and (7x2−5x+4)

Solution: 

Given Polynomials:

(3x+5) , (2x−3) and (4x−6)

To find: The addition of polynomials

\(\begin{aligned}
& (3 x+5)+(2 x-3)+(4 x-6) \\
& (3 x+5)+(2 x-3)+(4 x-6)=3 x+5+2 x-3+4 x-6 \\
& (3 x+5)+(2 x-3)+(4 x-6)=3 x+2 x+4 x+5-3-6 \\
& (3 x+5)+(2 x-3)+(4 x-6)=9 x-4
\end{aligned}\)

The addition of polynomials: (3x+5) + (2x−3) + (4x−6) = 9x − 4

Page 5 Exercise 4 Answer

Question: Find The Addition And Subtract Of The Polynomial (3x2+5x−2) and (7x2−5x+4)

Solution: 

Given Polynomials:

(a+b−c) + (a+b+2c) − (a+b+c)

To find: The addition and subtraction of polynomials

(a+b-c)(a+b+2c)-(a+b+c)

(a+b-c) + (a+b+2c) – (a+b+c) = a + b-c+a+b+2c-a-b-c

(a+b-c)+(a+b+2c)-(a+b+c)=a+a-a+b+b-b-c+2c-c

(a+b-c)+(a+b+2c)-(a+b+c)=a+b

(a+b-c)+(a+b+2c)-(a+b+c)= a+b

Page 5 Exercise 6 Answer

Question: Subtract The Polynomial (3x2+5x−2) and (7x2−5x+4)

Solution: 

Given Polynomials:

(x−y−z) + (x−y−z) − (x−y−z) + (x+y+z)

To find: The addition and subtraction of polynomials

(x-y-z)+(x-y-z)-(x-y-z)+(x+y+z)

(x-y-z+(x-y-z)-(x-y-z)+(x+y+z)=x-y-z-x+y+z+x +y+z

(x-y-z)+(x-y-z)-(x-y-z)+(x+y+z)=x+x-x-y-y+y-7-z+7+7

(x-y-z)+(x-y-z)-(x-y-z)+x+y+z)=2x

(x-y-z) + (x-y-z) – (x – y – z) + (x + y + z) = 2x

Page 5 Exercise 7 Answer

Question: Subtract The Polynomial (3x2+5x−2) and (7x2−5x+4)

Solution: 

Given Polynomials:

(3a2+2b+4) − (a2+b−1) − (a2+2b−1) − (a2+b−2)

To find: The Subtraction of polynomials

(x-y-z)+(x-y-z)-(x-y-z)+(x+y+z)

(x-y-z)+(x-y-z)-(x-y-z)+(x+y+z)=x-y-z+x-y-z-x+y+z+x+y+z

(x-y-z)+(x-y-z)-(x-y-z)+(x+y+z)=x-x-x+x-y-y+y-z-z+z+z

(x-y-z)+(x-y-z)-(x-y-z)+(x+y+z)=2x

(3a2+2b+4) − (a2+b−1) − (a2+2b−1) − (a2+b−2) = -2b + 8

Page 5 Exercise 8 Answer

Question: Subtract The Polynomial (3x2+5x−2) and (7x2−5x+4)

Solution: 

Given Polynomials:

8x − (5x−4) = 25

To find: Value Of x

Given:

\(\begin{aligned}
& 8 x-(5 x-4)=25 \\
& 8 x-(5 x-4)=8 x-5 x+4 \\
& 8 x-(5 x-4)=3 x+4
\end{aligned}\)

3x+4=25

3x=21

\(x=\frac{21}{3}\)

x=7

The Value of x is = 7

Page 5 Exercise 9 Answer

Question: Subtract The Polynomial (3x2+5x−2) and (7x2−5x+4)

Solution: 

Given Polynomials:

6x − (4x−5) = 13

To find: The value

To solve the equation:

6x-(4x-5)=13

6x-(4x-5)=6x-4x+5

6x-(4x-5)=2x+5

⇒ 2x+5=13

⇒ 2x=13-5

⇒ 2x=8

⇒ \(x=\frac{8}{2}\)

⇒ x=4

The Value of x = 4

Page 5 Exercise 10 Answer

Question: Solve The Equation 10x − (3x+6) = 8 and find The Value Of X ?

Solution: 

Given Polynomials:

10x − (3x+6) = 8

10x-(3x+6)=8

10x-(3x+6)=10x-3x -6

10x-(3x+6)=7x-6

⇒ 7x-6=8

⇒ 7x=8+6

⇒7x=14

⇒x=\(\frac{14}{7}\)

⇒ x=2

The Value of x = 2

Page 5 Exercise 11 Answer

Question: The Subtraction Of Polynomials (6x+9) − (2x−5) = 38. Then Find The Value Of x?

Solution: 

Given Equation:

(6x+9) − (2x−5) = 38

To find: Value Of x

(6x+9)-(2x-5)=38

(6x+9)-(2x-5)=6x+9-2x+5?

(6x+9)-(2x-5)=4x+14

⇒ 4x+14=38

⇒4x=38-14

⇒4x=24

⇒x=\(\frac{24}{4}\)

⇒ x=6

Solution: x = 6

How To Solve Chapter 4 Subtracting Polynomials Key To Algebra Book 4

Page 5 Exercise 12 Answer

Question: The Subtraction Of Polynomials (9x+10) − (3x+2) = 74, Then Find The Value Of x?

Solution: 

Given Equation:

(9x+10) − (3x+2) = 74

To find: Value Of X

(9x+10)-(3x+2)=74

(9x+10)-3x+2)=9x+10-3x-2

(9x+10)-(3x+2)=6x+8

⇒6x+8=74

⇒6x=74-8

⇒6x=66

⇒ \(x=\frac{66}{6}\)

⇒ x=11

The Value of x = 11

Page 5 Exercise 13 Answer

Question: Find The Perimeter The Sides Are Given Here (3k+4),(2k−1),(3k+4),(2k−1)

Solution: 

Given sides: (3k+4),(2k−1),(3k+4),(2k−1)

To find: The perimeter

To find the perimeter add the following polynomials:

(3k+4),(2k-1),(3k+4),(2k-1)

(3k+4)(2k-1)+(3k+4)+(2k-1)=3k+4+2k-1+3k+4+2k-1

(3k+4)+(2k-1)+(3k+4)+(2k-1)=3k+2k+3k+2k+4-1+4-1

(3k+4)(2k-1)+(3k+4)+(2k-1)=10k+6

The perimeter: 10k + 6

Page 6 Exercise 14 Answer

Question: Find The Perimeter. The Sides Are Given Here (4x−3),(4x−3),(4x−3),(4x−3)?

Solution: 

Given:

The sides: (4m+7),(2m),(5m+7),(2m+1)

To find: The perimeter

(4m+7),(2m),(5m+7),(2m+1)

(4m+7)(2m)+(5m+7)+(2m+1)=4m+7+2m+5m+7+2m+1

(4m+7)+(2m)+(5m+7)+(2m+1)=4m+2m+5m+2m+7+7+1

(4m+7)+(2m)+(5m+7)+(2m+1)=13m+15

The perimeter: 13m + 15

Page 6 Exercise 15 Answer

Question: Find The Perimeter. The Sides Are Given Here (4x−3),(4x−3),(4x−3),(4x−3)?

Solution: 

Given:

The sides: (4x−3),(4x−3),(4x−3),(4x−3)

To find: The perimeter

(4x−3),(4x−3),(4x−3),(4x−3)

(4x-3)+(4x-3)+(4x-3)+(4x-3)=4x-3+4x-3+4x-3+4x-3+4x-3

(4x-3)+(4x-3)+(4x-3)+(4x-3)=4x+4x+4x+4x-3-3-3-3

(4x-3)+(4x-3)+(4x-3)+(4x-3)=16x-12

The perimeter: 16x − 12

Mcgraw Hill Algebra Book 4 Chapter 4 Explanations

Page 6 Exercise 16 Answer

Question: Find The Perimeter. The Sides Are Given Here  (2x+1),(2x+1),(2x+1),(2x+1),(2x+1),(2x+1)?

Solution: 

Given:

The sides: (2x+1),(2x+1),(2x+1),(2x+1),(2x+1),(2x+1)

To find: The perimeter

(2x+1),(2x+1),(2x+1),(2x+1),(2x+1),(2x+1)

(2x+1)+(2x+1)+(2x+1)(2x+1)=2x+x+2x+12x+x+2x+1+2x+1

(2x+1+(2x+1)(2x+1)+(2x+1)=2x+2x+2x+2x+2x+1+1+1+1+1+1+

(2x+1)+(2x+1)+(2x+1)+2x+1)+(2x+1)=12x+6

The perimeter: 12x + 6

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 3 Opposites Of Polynomials

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 3 Opposites Of Polynomials

Page 3 Exercise 1 Answer

Question: Find The Opposite Of Polynomial 3x2 − 8x + 2

Solution:

Given Polynomial:

3x2 − 8x + 2

To find: The opposite polynomial

3x²-8x+2

(3x²-8x+2)×(-1).3x²-(-1).8x+(-1).2

(3x²-8x+2)×(-1)=-3x²+8x-2-4

(3x²+5x-2)-(7x²-5x+4)= 3x²-7x²+5x-2-4

(3x²+5x-2)-(7x²-5x+4)=-4x²+10x-6

The opposite polynomial: −3x2 + 8x − 2

Mcgraw Hill Key To Algebra Book 4 Chapter 3 Solutions

Page 3 Exercise 2 Answer

Question: Find The Opposite Of Polynomial 6a + 7b + 4

Solution:

Given Polynomial:

6a + 7b + 4

To find: The opposite polynomial

6a+7b+4

(6a+7b+4)(-1)=(-1).6a+(-1).7b+(-1).4

(6a+7b+4)x(-1)=-6a-7b-4

The opposite polynomial: −6a − 7b − 4

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 3 Opposites Of Polynomials

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 3 Opposites Of Polynomials Page 3 Exercise 3 Answer

Question: Find The Opposite Of Polynomial 5x2 − 2x − 9

Solution:

Given Polynomial:

5x2 − 2x − 9

To find: The opposite polynomial

5x2-2x-9

(5x2-2x-9)(-1)=(-1).5x2– (-1).2x- (-1).9

(5x2-2x-9)(-1)=-5x2+2x+9

The opposite polynomial: −5x2 + 2x + 9

Key To Algebra Book 4 Opposites Of Polynomials Chapter 3 Answers

Page 3 Exercise 4 Answer

Question: Find The Opposite Of Polynomial x2 − 16

Solution:

Given Polynomial:

x2 − 16

To find: The opposite polynomial

x²-16

(x²-16)x(-1)=(-1).x²-(-1).16

(x²-16)x(-1)=-x²+16

The opposite polynomial: −x2 + 16

Page 3 Exercise 5 Answer

Question: Find The Opposite Of Polynomial x5 + x4 + x3 − x2 + x − 1

Solution:

Given Polynomial:

x5 + x4 + x3 − x2 + x − 1

To find: The opposite polynomial

⇒ \(\begin{aligned}
& x^5+x^4+x^3-x^2+x-1 \\
& \left(-x^5+x^4+x^3-x^2+x-1\right) x(-1)=(-1) x^5+(-1) \cdot x^4+(-1) \cdot x^3-(-1) \cdot x^2+(-1) \cdot x-(-1) \cdot 1 \\
& \left(x^5+x^4+x^3-x^2+x-1\right) x(-1)=-x^5-x^4-x^3+x^2-x+1
\end{aligned}\)

The opposite polynomial: −x5 − x4 − x3 + x2 − x + 1

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 3 Opposites Of Polynomials Page 3 Exercise 6 Answer

Question: Find The Opposite Of Polynomial −7x − 8

Solution:

Given Polynomial:

−7x − 8

To find: The opposite polynomial

(-7x-8)×(-1)=-(-1).7x-)(-1).8

(-7x-8)x(-1)=7x+8

The opposite polynomial: 7x + 8

Page 3 Exercise 7 Answer

Question: Find The Opposite Of Polynomial x2 + 5x − 14

Solution:

Given Polynomial:

x2 + 5x − 14

To find: The opposite polynomial

x²+5x-14

⇒ \(\begin{aligned}
& \left(x^2+5 x-14\right)(-1)=(-1) \cdot x^2+(-1) \cdot 5 x-(-1) \cdot 14 \\
& \left(x^2+5 x-14\right)(-1)=-x^2-5 x+14
\end{aligned}\)

The opposite polynomial: −x2 − 5x + 14

Chapter 3 Opposites Of Polynomials Mcgraw Hill Algebra Key

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 3 Opposites Of Polynomials Page 3 Exercise 8 Answer

Question: Find The Opposite Of Polynomial −x2 − 5x + 14

Solution:

Given Polynomial:

−x2 − 5x + 14

To find: The opposite polynomial

-x2 -5x+14

\(\begin{aligned}
& \left(-x^2-5 x+14\right) \times(-1)=-(-1) x^2-(-1) 5 x+(14) \cdot(-1) \\
& \left(-x^2-5 x+14\right) \times(-1)=x^2+5 x-14
\end{aligned}\)

The opposite polynomial: x2 + 5x − 14

Page 3 Exercise 9 Answer

Question: Find The Opposite Of Polynomial (x2+5x−14) + (−x2−5x+14)

Solution:

Given Polynomial:

(x2+5x−14) + (−x2−5x+14)

To find: Addition of opposite polynomials

(x2+5x−14) + (−x2−5x+14)

(x2+5x−14) + (−x2−5x+14)=(1-1)x²+(5-5)x+(-1+1)14

(x2+5x−14)+(−x2−5x+14)=0.x²+0.x+0.14

(x2+5x-14)+(-x2-5x+14)=0

The addition of opposite polynomial: (x2+5x−14) + (−x2−5x+14) = 0

Key To Algebra Book 4 Chapter 3 Opposites Of Polynomials Problems

Page 3 Exercise 10 Answer

Question: Find The Opposite Of Polynomial (−7x−8) + (7x+8)

Solution:

Given Polynomial:

(−7x−8) + (7x+8)

To find: Addition of opposite polynomials

(-7x-8)+(7x+8)

(-7x-8)+(7x+8)=(-7+7).x+(-1+1).8

(-7x-8)+(7x+8)=0.x+0.8

(-7x-8)+7x+8)=0

The addition of opposite polynomial: (−7x−8) + (7x+8) = 0

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 1 Polynomials

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 1 Polynomials Page 1 Exercise 1 Answer

Question 1: Find the Degree Of The Polynomial  x2 − 4 ?

Solution:

Given expression is x2 − 4.

We Need To find: Degree of x2 − 4.

\(x^2-4=x^2+0 \times x^1-4 x x^0\)

Highest power=2

Therefore, the degree of the polynomial X2-4 of x is 2.

Hence, x2 − 4 is a 2-degree polynomial.

Mcgraw Hill Key To Algebra Book 4 Chapter 1 Solutions

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 1 Polynomials Page 1 Exercise 2 Answer

Question 2: Find the Degree Of The Polynomial x2 − 5x + 2 ?

Solution:

Given algebraic expression is x2 − 5x + 2.

We Need To find: Degree of x2 − 5x + 2.

\(x^2-5 x+2=x^2-5 \times x^1+2 \times x^0\)

Highest power =2

Therefore, the degree of the given polynomial is 2

Hence, x2 − 5x + 2 is a 2-degree polynomial in x.

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 1 Polynomials

Key To Algebra Book 4 Polynomials Chapter 1 Answers

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 1 Polynomials Page 1 Exercise 3 Answer

Question 3: Find the Degree Of The Polynomial  6x4 ?

Solution:

Given algebraic expression is 6x4

We Need To find: Degree of 6x4

⇒ \(6 x^4=6 x x^4+0 \times x^3+0 \times x^2+0 \times x^1+0 \times x^0\)

highest power =4

Therefore, the degree of the given polynomial is 4

Hence, 6x4 is a 4-degree polynomial in x.

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 1 Polynomials Page 1 Exercise 4 Answer

Question 4: Find the Degree Of The Polynomial  x+5?

Solution:

Given algebraic expression is x+5

We Need To find: Degree of x+5

\(x+5=1 \times x^1+5 \times x^0\)

Highest power =1

Therefore, the degree of the polynomial is 1

Hence, x+5 is a 1-degree polynomial in x.

Chapter 1 Polynomials Mcgraw Hill Algebra Key

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 1 Polynomials Page 1 Exercise 5 Answer

Question 5: Find the Degree Of The monomial  8?

Solution:

Given algebraic expression is 8

We Need To find: Degree of 8

8x=8×x0

Highest power =0

Therefore, the degree is 0.

Hence, the 8 is a zero-degree polynomial in x.

How To Solve Chapter 1 Polynomials Key To Algebra Book 4

Mc Graw Hill Key To Algebra Book 4 Polynomials 1st Edition Chapter 1 Polynomials Page 1 Exercise 6 Answer

Question 6: Find the Degree Of The Polynomial  5x3 + 2x2 − 4x ?

Solution:

Given algebraic expression is 5x3 + 2x2 − 4x

We Need To find: Degree of 5x3 + 2x2 − 4x

5x3 + 2x2 − 4x =\(5 \times x^3+2 \times x^2-4 \times x^1+0 \times x^0\)

Highest power =3

Therefore, the degree of the given polynomial is 3

Hence, 5x3 + 2x2 − 4x is a 3-degree polynomial in x.

Envision Algebra 1 Assessment Readiness Workbook Student Edition Chapter 4

Envision Algebra 1 Assessment Readiness Workbook Chapter 4

Page 52 Exercise 1 Answer

In the question, five numbers are given as,

1. \(\frac{1}{7}\)

2. √3

3. √15

4. √25

5. \(\frac{2}{3}\)

It is required to find which of the given numbers are irrational.

To find this, consider each number and check whether it can be reduced to any ratio between an integer p and a natural number q. If it is possible, the number is not irrational.

Consider the number \(\frac{1}{7}\) and check whether it can be reduced to any ratio between an integer p and a natural number q.

The number \(\frac{1}{7}\) is in the form \(\frac{p}{q}\).

So, it is rational.

\(\frac{1}{7}\) is rational.

Consider the number √3 and check whether it can be reduced to any ratio between an integer p and a natural number q.

√3 cannot be reduced to any ratio between an integer p and a natural number q.

Envision Algebra 1 Assessment Readiness Workbook Student Edition Chapter 4

So, √3 is irrational.

Consider the number √15 and check whether it can be reduced to any ratio between an integer p and a natural number q.

√15 = √3 × √5, both terms are irrational since they cannot be reduced to any ratio between an integer p and a natural number q.

So,√15 is irrational.

Consider the number √25 and check whether it can be reduced to any ratio between an integer p and a natural number q.

√25 = 5

5 can be written in \(\frac{p}{q}\) form as \(\frac{5}{1}\).

So, √25 is rational.

Consider the number \(\frac{2}{3}\) and check whether it can be reduced to any ratio between an integer p and a natural number q.

The number \(\frac{2}{3}\) is in the form \(\frac{2}{3}\).

So, it is rational.

\(\frac{2}{3}\) is rational.

By considering each number and checking whether it can be reduced to any ratio between an integer p and a natural number q, it is found that numbers (B)√3 and  (C) √15 are irrational.

Envision Algebra 1 Chapter 4 Answer Key

Envision Algebra 1 Assessment Readiness Workbook Student Edition Chapter 4 Page 52 Exercise 2 Answer

In the question, \(\frac{(3)^{-4}(7)^{-2}}{(3)^2(7)^{-5}}\) is given. And four forms are as

1. \(\frac{7^7}{3^6}\)

2. \(\frac{7^3}{3^6}\)

3. \(\frac{3^2}{7^3}\)

4. \(\frac{3^6}{7^7}\)

It is required to rewrite \(\frac{(3)^{-4}(7)^{-2}}{(3)^2(7)^{-5}}\) using positive exponents.

Given \(\frac{(3)^{-4}(7)^{-2}}{(3)^2(7)^{-5}}\)

Exponential formula \(a-b=\frac{1}{a^b}\)

Apply the exponential formula \(a-b=\frac{1}{a^6} \text { to } \frac{(3)^{-4}(7)^{-2}}{(3)^2(7)^{-5}}\)

⇒ \(\frac{(3)^{-4}(7)^{-2}}{(3)^2(7)^{-5}}=\frac{(7)^5}{(7)^2(3)^2(3)^4}\)

Apply the exponential formula \(\frac{a^m}{a^n}=a^{m-n} \text { and } a^m a^n=a^{m+n} \text { to } \frac{(7)^5}{(7)^5(3)^2(3)^4}\)

⇒ \(\begin{aligned}
\frac{(7)^5}{(7)^2(3)^2(3)^4} & =\frac{(7)^{5-2}}{(3)^{2+4}} \\
& =\frac{(7)^3}{(3)^6}
\end{aligned}\)

Using exponential equations \(\frac{1}{a^b}\), \(\frac{a^m}{a^n}\) = am-n and aman= am+n,

⇒ \(\frac{(3)^{-4}(7)^{-2}}{(3)^2(7)^{-5}}\) can be rewritten as \(\frac{(7)^{3}}{(3)^{6}}\)

Page 52 Exercise 3 Answer

In the question, an equation is given as ∣2x−3∣ − 4 = 3 and four solutions are given as

1. −3

2. −2

3. 3

4. 5

5. 6

It is required to find the solution of the given equation.

To find this, first find the modulus value of ∣2x−3∣. Then two values are obtained. Take these two values as two cases and find the value of x from both cases.

Given |2x-3|-4=3
|2x-3|-4=3
|2x-3|=3+4
|2x-3|=7

So, talking modulus 2x-3=±7

Take the value 2x-3 as 7 and find the value of x

2x-3=7
2x=7+3
2x=10

Divide 2 on both sides

⇒ \(\frac{2 x}{2}=\frac{10}{2}\)

Take the value 2x-3 as-7 find the value of x

2x-3=-7
2x=-7+3
2x=-4

Divide 2 on both sides

\(\frac{2 x}{2}=\frac{-4}{2}\)

x=-2

By using the equation ∣x∣ = ±x, the two solutions obtained are

(B) x = −2 and

(D)x = 5

Envision Algebra 1 Assessment Readiness Workbook Student Edition Chapter 4 Page 52 Exercise 4 Answer

In the question, it is given that a line passes through two points (4,−1) and (−4,3).

Also, four equations are given as

1. y = \(\frac{1}{2} x-1\)

2. y = 2x – 1

3. y = \(\frac{-1}{2} x-1\)

4. y = -2x -1

It is required to find which equation represents a line perpendicular to a line that passes through (4,−1) and (−4,3).

To solve this, first find the slope of the line passes through (4,−1) and (−4,3) using the equation m = \(\frac{y_2-y_1}{x_2-x_1}\) and then use this slope to find the slope of the line perpendicular to the line passes through (4, -1) and (-4, 3) using the equation m1 = \(\frac{-1}{m}\).

The slope of the line passes through (4,-1) and (4,3) using the equation.

m= \(\begin{aligned}
& m=\frac{y_2-y_1}{x_2-x_1} \\
& m=\frac{3-(-1)}{-4(-4)} \\
& m=\frac{3+1}{-4-(4)}
\end{aligned}\)

Reducing \(\frac{4}{-8}=\frac{-1}{2}\)

The slope of line passing through (4,-1) and (-4,3) is \(\frac{-1}{2}[\)

Slope of the line passing through (4,−1) and (−4,3) is m = \(\frac{-1}{2}\).

Find the slope m1 of the line perpendicular to the line having slope m using the equation m1= \(\frac{-1}{m}\).

m1 = \(-\frac{1}{\left(-\frac{1}{2}\right)}\)

= 2

Find the equation of the line with slope 2 from the given options.

Since the slope of the line is 2, the equation satisfying is y = 2x − 1.

The slope of the line passing through(4,−1) and (−4,3) using the equation m = \(\frac{y_2-y_1}{x_2-x_1}\) is found as m = \(\frac{-1}{2}\).

The slope of the line perpendicular to the line having slope m using the equation m1 = \(-\frac{1}{\left(-\frac{1}{2}\right)}\), is found as m1 = 2.

Since the slope of the line is 2, the equation satisfying is (B) y = 2x − 1.

Page 52 Exercise 6 Answer

In the question, an expression (6x4y6)2 is given. Also, four options are given as

1. 6x6y8

2. 12x8y12

3. 36x8y12

4. 36x6y8

It is required to simplify (6x4y6)2 and to find which of the four options is right.

To solve this, use the equation (abc)n = anbncn to the given expression and simplify it using mathematical operations.

Given (6x4y6

Apply the equation (abc)n = anbncn to (6x4y6

(6x4y6)² =(6)².(x4)².(y6
(6x4y6)²=36x8y12

So, (6x4y6)²=36x8y12

Using the exponential equations (abc)n = anbncn and

(ab)c= abc, (6x4y6)2 can be simplified as 36x8y12.

So (C) 36x8y12 is the correct option.

Page 53 Exercise 7 Answer

In the question, a function is given as f(x) = ∣−x+7∣.

Also, four piecewise functions are given as

1. g(x) = \(\left\{\begin{array}{l}
-x+7, \text { if } x \leq-7 \\
x-7 \text {,if } x>-7
\end{array}\right.\)

1. g(x) = \(\left\{\begin{array}{l}
-x+7 \text {, if } x \leq 7 \\
x-7, \text { if } x>7
\end{array}\right.\)

1. g(x) = \(\left\{\begin{array}{l}
-x+7 \text {, if } x \geq 0 \\
x-7 \text {, if } x<0
\end{array}\right.\)

1. g(x) = \(\left\{\begin{array}{l}
-x+7 \text {, if } x \geq 7 \\
x-7 \text {, if } x<7
\end{array}\right.\)

It is required to identify the piecewise function that has the same graph as the function f(x) = ∣−x+7∣.

To solve this, the function will break when the term in the modulus becomes zero.

Find the value of x when the modulus becomes 0 and find the function value to the left and right of the x value.

Find the value of x when the modulus becomes 0.

Given f(x)=|-x+7|

Find the value of when the models become o

=-x+7=0
x=7

so, the function breaks art x=7
find the function value when x<7.

​if x<7
f(x)=-(-x+7
f(x)=x-7
i.e., f(x)=x-7,if x<7

Find the function value when x ≥ 7.

f(x) = −x+7.

i.e., f(x) = −x+7,if x ≥ 7.

The piecewise function having the same graph as f(x) = ∣−x+7∣ is

1. g(x) = \(\left\{\begin{array}{l}
-x+7 \text {, if } x \geq 7 \\
x-7 \text {, if } x<7
\end{array}\right.\)

Envision Algebra 1 Assessment Readiness Workbook Student Edition Chapter 4 Page 53 Exercise 8 Answer

In the question, a function f(x) = 2x is given.

It is required to state which type of function is f(x) = 2x

The general equation of the exponential function is f(x) = ax

Comparing the given function with the general equation of the exponential function f(x) = ax, it is found that

f(x) = 2x is an exponential function with the value of a 2.

By Comparing the given function with the general equation of the exponential function f(x) = ax, it is found that f(x) = 2x is an exponential function with the value of a is 2.

Page 53 Exercise 9 Answer

In question four scores of a student are given as 89, 98, 93, and 97 and the average of five scores is given as 94.

It is required to find what score must the student earn on the fifth test to have an average score of 94.

To find this, let the score of the fifth subject be x. Substitute this in the equation of average score and find x.

Let x be the fifth score and substitute it in the equation of the average score.

​Average score \(=\frac{\text { total score }}{\text { number of Scores }}\)

⇒ \(94=\frac{89+98+93+97+x}{5}\)

⇒ \(94=\frac{377+x}{5}\)

94×5=377+x

Simplify the above equation and find x

470=377+x
x=470-377
x=93

So, the fifth score is 93.

Letting the fifth score as x and substituting it in the equation of average score, the fifth score is found as 93 to get an average of 94.

Envision Algebra 1 Assessment Readiness Workbook Student Edition Chapter 4 Page 53 Exercise 10 Answer

In the question, a graph is given.

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 53 Exercise 10 Answer Image 1

Four equations are given as

y = −∣3x∣ + 2

y = ∣3x+2∣

y = −3∣x+2∣

y = ∣3x∣ + 2

It is required to find the correct equation of the graph.

To find this, first find the coordinates from the given graph and find the equation of the line using the two-point form of a line (y – y1) = \(\left(\frac{y_2-y_1}{x_2-x_1}\right)\left(x-x_1\right)\).

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 53 Exercise 10 Answer Image 2

Find the coordinates from the given graph.
The coordinates are (0,2), (\(\frac{2}{3}\), 0) and (\(\frac{-2}{3}\), 0).

Find the equation of the line passing through (0,2) and (\(\frac{2}{3}\), 0) using two-point form of the line.

⇒ \(\left(y-y_1\right)=\left(\frac{y_2-y_1}{x_2-x_1}\right)\left(x-x_1\right)\)

⇒ \((y-2)=\left(\frac{0-2}{\frac{2}{3}-0}\right)(x-0)\)

⇒ \((y-2)=\frac{-2}{\frac{2}{3}} x\)

(y-2)=-3x

Find the equation of the line passing through (0,2)(0,2) and (\(\frac{-2}{3}\), 0) using the two-point form of the line.

⇒ \(\left(y-y_1\right)=\left(\frac{y_2-y_1}{x_2-x_1}\right)\left(x-x_1\right)\)

⇒ \((y-2)=\left(\frac{0-2}{\frac{-2}{3}-0}\right)(x-0)\)

⇒ \((y-2)=\frac{-2}{\frac{-2}{3}} x\)

(y-2)=3x

Write the two equations in the modulus form.

The equations are (y−2) = −3x and

(y−2) = 3x

−3x ≤ y−2 ≤ 3x

So, the resultant equation can be written as y = ∣3x∣+2.

By finding the coordinates from the given graph and applying a two-point form of the line (y – y1) = \(\left(\frac{y_2-y_1}{x_2-x_1}\right)\left(x-x_1\right)\), the equation of the graph is found as y = |3x|+2.

So, the correct equation is (D) y = |3x|+2.

Page 53 Exercise 11 Answer

In the question, a scatter point graph is given with four options.

1. y = x + 2

2. y = −x + 2

3. y = 2x + 2

4. y = −2x + 2

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 53 Exercise 11 Answer Image 1

 

It is required to find the best estimation of the equation of the fit line from given options.

To solve the question, draw a line that approximately divides the scatter points in half. Now find the equation of this line and compare it with the given options.

Draw a best-fit line of the scatter points.

The line should be drawn in this way so that it approximately divides the number of points in half on both sides of the line.

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 53 Exercise 11 Answer Image 2

Find the equation of the line.

Extend the line so that it touches the x-axis. Now two points on the line are (0,2) and (−1,0).

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 53 Exercise 11 Answer Image 3

The slope of the line is

\(\frac{0-2}{-1-0}=\frac{-2}{-1}\)

= 2

And the y-intercept is 2.

Thus, the equation of the line is y = 2x + 2.

Therefore, option C) y = 2x + 2 is the best-estimated equation for the given scatter points which was solved using the general equation of line and slope of the line.

Envision Algebra 1 Assessment Readiness Workbook Chapter 4 Solutions

Envision Algebra 1 Assessment Readiness Workbook Student Edition Chapter 4 Page 43 Exercise 12 Answer

In the question, six numbers \(\frac{-1}{4}\), -1, √3. √-8, \(\frac{1}{2}\), 3 are given.

It is required to arrange the numbers from least to greatest.

To solve the question, convert all numbers in decimal format. Then arrange the number from least to greatest.

Arrange the numbers from least to greatest.

Numbers are \(\frac{-1}{4}\), -1, √3, √-8, \(\frac{1}{2}\), 3.

Using a calculator, write numbers as decimals, -0.25, -1, 1.732, -2.828, 0.5, 3.

Now arrange in ascending order −2.828, −1, −0.25, 0.5, 1.732,3

Thus, the numbers order from least to greatest are −√8, -1, \(\frac{-1}{4}\), \(\frac{1}{2}\), √3, 3.

Thus, the numbers order from least to greatest are −√8, -1, \(\frac{-1}{4}\), \(\frac{1}{2}\), √3, 3 which was solved by first converting numbers into decimal and then arranging.

Page 54 Exercise 13 Answer

In the question, a dot plot of data is given.

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 54 Exercise 13 Answer Image 1

It is required to find the mean and median of the data shown in the above figure to the nearest hundredth.

To solve the question, make a table of given data. Then find the mean and median using suitable formulas and mathematical operations.

Make a table of the given data.

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 54 Exercise 13 Answer Image 2

Find the mean of the data.

Mean \(\bar{x}=\frac{\sum f_i x_i}{\sum f_i}\)

⇒ \(\bar{x}=\frac{138}{13}\)

⇒\(\bar{x}=11.5\)

Thus, the mean of the data nearest to the hundredth is 11.50.

Find the median of the data.

Since the sum of the frequencies n is 13, which is an odd number.

Then the median is at the position

⇒ \(\left(\frac{13+1}{2}\right)^{t h}=7^{t h}\).

The number in the 7th position is 10.

Therefore, the median nearest to the hundredth is 10.00.

Therefore, the mean of the data nearest to the hundredth is $11.50$ and the median nearest to the hundredth is $10.00$. They are different as the mean gives the average value of data and the median gives the middle number of data which were solved using formulas of mean and median.

Page 54 Exercise 14 Answer

In the question, the area of the rectangle is represented by a quadratic equation, 12x2 + x − 6, and the width of the rectangle is represented as 3x−2.

It is required to find the width of the rectangle.

To solve the question, find the roots of the quadratic equations using quadratic formulas. Then write the equation as a product of its factors using its roots.

Find the roots of the quadratic equation.

Given equation is 12x²-x+6

⇒ \(x=\frac{-1 \pm \sqrt{1^2-4(12)(6)}}{2(12)}\)

⇒ \(\begin{aligned}
& x=\frac{-1 \pm \sqrt{1+288}}{24} \\
& x=-1 \pm 17
\end{aligned}\)

Solving further to calculate roots

⇒ \(\begin{aligned}
& x=\frac{-1+17}{24} \\
& x=\frac{16}{24} \\
& x=\frac{2}{3}
\end{aligned}\)

Solving further to calculate another root

⇒ \(\begin{aligned}
& x=\frac{-1-17}{24} \\
& x=\frac{-18}{24} \\
& x=\frac{-3}{4}
\end{aligned}\)

Solve further take x= \(\frac{2}{3}\)

Multiply by 3 and then subtract by 2

3x-2=0

⇒ \(x=\frac{-3}{4}\)

Multiply by 4 and then add by 3 4x+3=0.

Find the length of the square.

Now, the quadratic equation can be factored as

12x2 + x − 6 = (4x+3)(3x−2)

On comparing with the formula,

A = l × b

So, the length is 4x+3 units.

Thus, the length of the rectangle is 4x+3 units which was solved using the quadratic formula and then finding factors of the equation.

Envision Algebra 1 Assessment Readiness Workbook Student Edition Chapter 4 Page 54 Exercise 15 Answer

In the question, a linear inequality, 2x+4y < 4, is given.

It is required to graph the inequality.

To solve the question, rearrange the equation so that on the left side there is a y variable, and everything else on the right. Then plot the inequality as a simple linear equation. Then shade the graph above the line for a ‘greater than’ inequality and below the line for a ‘less than’ inequality.

Rearrange the equation.

It should be done so that on the left side there is a y variable, and everything else on the right.

Given inequality is 2x+4y<4

Subtract 2x from both sides

4y<4-2x

Divide by 4 on both sides

⇒ \(\begin{aligned}
\frac{4 y}{4} & <\frac{4}{4}-\frac{2 x}{4} \\
y & <1-\frac{1}{2} x
\end{aligned}\)

A simple linear equation of the above inequality can be written as y = 1 – \(\frac{1}{2} x\).

Plot the equation on the graph.

y = 1 – \(\frac{1}{2} x\)

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 54 Exercise 15 Answer Image 1
Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 54 Exercise 15 Answer Image 2
The line in the above graph is dashed as the inequality 4y < 4−2x contains < not ≤.

Solve further.

As the inequality, 4y < 4 − 2x, contains less than sign, the shaded area is

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 54 Exercise 15 Answer Image 3

Thus, the graph of the linear inequality 2x+4y < 4 is sketched which was solved by first plotting a simple equation and then shading the region.

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 54 Exercise 15 Answer Image 3

 

Page 54 Exercise 16 Answer

In the question, a function f(x) = x2 − 4x + 5 is given.

It is required to graph the function.

To solve the question, convert the given equation into a general equation of the parabola.

Convert the given equation into a general equation of the parabola.

Given function can be written as

y = x2 − 4x + 5

Now add and subtract the square of half of the coefficient of x in the equation.

Given function f(x) = x²-4x+5
Given function can be written as

y=x2-4x+5+22-22

y=x2-4x+4+5-4
y=x2-4x+4+5-4
y=x2-4x+4+1

Solve further to get it in general form

y= x2-2(2) x+22+1
y=(x-2)2+1

Find the value of the vertex of the parabola.

y = (x−2)2 + 1

By comparing it with the standard equation, the vertex (h,k) of the parabola is (2,1).

As a > 1, then the graph opens up.

Now plot the graph.

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 54 Exercise 16 Answer Image 1

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 54 Exercise 16 Answer Image 2

Therefore, a graph of the function f(x) = x2 − 4x + 5 is sketched which was solved using the standard equation of parabola.

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 54 Exercise 16 Answer Image 2

Envision Algebra 1 Assessment Readiness Workbook Student Edition Chapter 4 Page 55 Exercise 17 Answer

In the question, it is given that a ball is thrown directly upwards from a height of 2 feet and velocity is 16 feet per second, and equation h = −16t2 + 16t + 2.

It is required to find the time it takes for a ball to reach its maximum height and maximum height of the ball.

To solve the question, find the slope of the given equation and equate the obtained equation to zero to find the time t. Then substitute the obtained value of time in the given equation to find the maximum height.

Find the time that the ball takes to reach maximum height.

Given equation is h=-16t2+16t+2

⇒ \(\frac{d h}{d t}=-32 t+16\)

At maximum height \(\frac{d h}{d t}=0\)

-32t+16=0

Solve further
Subtract 16 from both sides
-32t=-16

Solve further
Subtract 16 from both sides

-32t=-16

Divide both sides by -32

⇒ \(\begin{gathered}
\frac{-32 t}{-32}=\frac{-16}{-32} \\
t=\frac{1}{2}
\end{gathered}\)

Thus, the time required to go to maximum height is 0.5 seconds.

Put t=0.5 in the equation

h=-16t2+16t+2
h=-16(0.5)2+16(0.5)+2
h=-16(0.25)+8+2
h=-4+10

Solve further

h=-4+10
h=6

Thus, the time required to go to maximum height is 0.5 second

The initial height is 2 feet.

So, the maximum height is

6 + 2 = 8 feet.

A. The ball takes 0.5 sec to reach its maximum height.

B. Maximum height reached is 8 feet which was solved using the concept of slope and first derivative.

Page 55 Exercise 18 Answer

In the question, a table is given.

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 55 Exercise 18 Answer Image 1

It is required to plot the data and find the estimation of the equation of the best-fit line.

To solve the question, plot the scatter points on a graph. Then draw a line that approximately divides the scatter points in half. Now find the equation of this line.

Plot the scatter points on a graph using a given table.

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 55 Exercise 18 Answer Image 2

 

Draw a best-fit line of the scatter points.

The line should be drawn in this way so that it approximately divides the number of points in half on both sides of the line.

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 55 Exercise 18 Answer Image 3

Find the equation of the line.

Extend the line so that it touches the x-axis. Now two points on the line are (0,6) and (6,0).

Slope of the line is

\(\frac{0-6}{6-0}=\frac{-6}{6}\)

= -1

And the y-intercept is 6.

Thus, the equation of the line is y = −x + 6.

Therefore, the graph of scatter points is plotted and y = -x + 6 is the best-estimated equation for the given scatter points which was solved using a general equation of the line and slope of the line.

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 55 Exercise 18 Answer Image 4

Envision Algebra 1 Student Edition Chapter 4 Practice Problems

Envision Algebra 1 Assessment Readiness Workbook Student Edition Chapter 4 Page 56 Exercise 19 Answer

In the question,  it is given that the length of the hypotenuse of the right triangle is 25cm and the measure of one leg is 20 cm.

It is required to find the length of the other leg.

To solve the question, put the value of the lengths of the leg and hypotenuse in the formula of Pythagoras’ theorem. Then solve using appropriate mathematical operations.

Find the length of the leg of the right triangle.

Put b as 20 and c as 25 in the Pythagoras theorem formula.

​a²+b²=c²
put b=20 and c=25

a²+20²=25²
a²+400=625

Subtract 400 from both sides

a²+400-400=625-400

a²=225

Take square root on both sides

⇒ \(\begin{aligned}
\sqrt{a^2} & =\sqrt{225} \\
a & =\sqrt{25^2} \\
a & = \pm 15
\end{aligned}\)

But measuring length cannot be negative. Thus, the measure of another leg of the right triangle is 15 units.

Thus, the measure of another leg of the right triangle is 15 units which was solved using Pythagoras theorem.

Page 56 Exercise 20 Answer

In the question, a quadratic equation 5x2 − 18x + 9 = −3 is given.

1. 0.37

2. 0.6

3. 0.88

4. 2.72

5. 3

6. 3.23

It is required to choose the correct solutions of the equation from the given options.

To solve the question, convert the given quadratic equation into the form ax2 + bx + c = 0. Then put values of a, b, and c in the quadratic formula to find the solutions.

Convert quadratic equations into general form.

Given 5×2-18x+9=-3
Add 3 on both sides
5×2-18x+9+3=-3+3
5×2-18x+12=0

Compared with the general equation

a=5,b=-18,c=12

⇒ \(x=\frac{-(-18) \pm \sqrt{(-18)^2-4(5)(12)}}{2(5)}\)

⇒ \(\begin{aligned}
& x=\frac{18 \pm \sqrt{324-240}}{10} \\
& x=\frac{18 \pm \sqrt{84}}{10}
\end{aligned}\)

use to calculate to evaluate

⇒ \(x=\frac{18 \pm 9.16}{10}\)

Solve further

⇒ \(\begin{aligned}
& x=\frac{18+9.16}{10} \\
& x=2.716 \\
& x=\frac{18-9 \cdot 16}{10} \\
& x=0.884
\end{aligned}\)

Thus, the solutions of the equation to the nearest hundredth are 2.72 and 0.88.

Thus, solutions of the equation to the nearest hundredth are C) 2.72 and D) 0.88 which were solved using a quadratic formula.

Envision Algebra 1 Assessment Readiness Workbook Student Edition Chapter 4 Page 56 Exercise 21 Answer

In the question it is given two equations namely, y = 3x + 3 and y = 3x.

It is required to conclude that how the graph of the equation y = 3x + 3 can be described as the transformation of the graph of equation y = 3x. To solve the question start with writing the given equations as f(x) and g(x) respectively.

Then, write the value of g(x) in terms of f(x) and compare it with the formula of vertical shift to get the required answer.

Write the first equation as f(x) and g(x) as the second equation.

​f(x) = 3x + 3

g(x) = 3x

Write f(x) in terms of g(x).

​f(x) = 3x + 3

f(x) = g(x) + 3

Now, rewrite the expression and find the value of g(x) in terms of f(x) by subtracting 3 from both sides of the equation.

​g(x) + 3 − 3 = f(x) − 3

g(x) = f(x) − 3

Use the formula that vertical shift depends upon the value of k.

g(x) = f(x) + k, which means the graph is shifted k units upwards.

g(x) = f(x) − k, which means the graph is shifted k units downwards.

From the above-calculated equation, it is clear that for the given equations g(x) = f(x) − 3, the shift is 3 units downwards.

The transformation of graph y = 3x + 3 as y = 3x can be described by a 3-unit downwards translation, so the correct option is C) translation 3 units down which was solved using the formula for the vertical shift.

Page 56 Exercise 22 Answer

In the question, it is given an equality as −2x + 5 < 1.

It is required to graph the solution of the inequality.

To solve the question, start with writing the given inequality and solve it using basic mathematical operations.

Finally, plot the obtained answer on the graph.

Write the given inequality.

Given inequality -2x+5<1

Add 2x to both sides

-2x+2x+5<1+2x

5<1+2x

Subtract 1 from both sides

5-1<1+2x-1

4<2x

Divide 2 on both sides

⇒ \(\frac{4}{2}<\frac{2 x}{2}\)

2<x

So the solution of the inequality lies on the right-hand side of the value 2 on the graph.

Plot the graph.

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 56 Exercise 22 Answer

The graph for the given inequality i.e. −2x + 5 < 1 is as shown and the solution for the equation is given by x > 2.

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 56 Exercise 22 Answer

Page 56 Exercise 24 Answer

In the question it is given that $500 has been deposited in an account that gives 2% interest compounded monthly.

It is required to use the formula A = \(P\left(1+\frac{r}{n}\right)^{n t}\) to determine how much money will be in the account after 5 years. To solve the question start with writing the given information in the question. Then substitute the given values in the formula. Simplify the formed equation using basic mathematical operations and a calculator to get the required answer.

According to the given

p=500
r=2%
n=12
t=5 years

Now substitute the given values into the formula

A= \(P\left(1+\frac{r}{n}\right)^{n t}\)

A= \(500\left(1+\frac{2}{12}\right)^{12(5)}\)

A= \(500\left(1+\frac{1}{6}\right)^{60}\)

A= \(500\left(\frac{6+1}{6}\right)^{60}\)

A=\(500\left(\frac{7}{6}\right)^{60}\)

A+500(10394.59)
A=51,97,295

So the amount calculated is $51,97,295.

When $500 is deposited as a principle in a bank with 2% interest compounded monthly, then after 5 years the amount accumulated in the account is calculated to be $51,97,295 which was solved using the formula A = \(P\left(1+\frac{r}{n}\right)^{n t}\)

Page 57 Exercise 25 Answer

In the question it is given two equations namely, y = \(\sqrt[3]{\frac{x}{6}}\) and y = \(\sqrt[3]{x}\).

It is required to conclude how the graph of the equation y = \(\sqrt[3]{\frac{x}{6}}\) can be described as the transformation of the graph of the parent function y = \(\sqrt[3]{x}\).

To solve the question start with writing the given equations as f(x) and g(x) respectively. Then, write the value of g(x) in terms of f(x) and compare it with the formula of the horizontal shift to get the required answer.

Write the parent equation as f(x) and g(x) as the second equation.

f(x) = \(\sqrt[3]{x}\)

g(x) = \(\sqrt[3]{\frac{x}{6}}\)

Now, rewrite the expression and find the value of g(x) interms of f(x) by substituting the value of x.

g(x) = \(\sqrt[3]{\frac{x}{6}}\)

g(x) = \(\sqrt[3]{\frac{1 x}{6}}\)

g(x) = \(f\left(\frac{x}{6}\right)\)

g(x) = \(f\left(\frac{1}{6} x\right)\)

Use the formula that for a parent function f(x). A new function g(x) = a⋅f(x), where a is a constant, results in a horizontal compression or vertical stretch of the function f(x).

a > 1, means the graph is horizontally stretched.

0 < a < 1, means the graph is horizontally compressed.

From the above-calculated equation, it is clear that for the given equations g(x) = \(f\left(\frac{1}{6} x\right)\).

so, a = \(\frac{4}{2}\)

Clearly. 0 < a < 1, so there is a horizontal compression by a factor of \(\frac{1}{a}\).

\(\frac{1}{a}\) = \(\frac{1}{\frac{1}{6}}\)

\(\frac{1}{a}\) = 6

Hence for the given equations of two graphs, the transformation from the parent function is horizontal compression by a factor of 6.

The transformation of graph \(\sqrt[3]{x}\) as y = \(\sqrt[3]{\frac{x}{6}}\) can be described by a horizontal compression by a factor of 6, so the correct option is B) horizontal compression by a factor of 6, which was solved using the formula for horizontal compression and stretch.

Envision Algebra 1 Assessment Readiness Workbook Student Edition Chapter 4 Page 57 Exercise 26 Answer

In the question, it is given a system of equations as y = −2x − 4 and y = −4x − 2.

It is required to find the solution of the system of these equations.

To solve the question, start by writing the given system of equations and substituting the value of y from one equation to another. Then, simplify the expression using basic mathematical operations until the value of x is obtained. Then substitute the value of x in any of the given equations to get the required answer.

​Given a system of equations

y=-2x-4
y=-4x-2
-4x-2=-2x-4

Add 4x on both sides

-4x-2+4x=-2x+4x-4
2x=2

divide 2 on both sides

⇒ \(\frac{2 x}{x}=\frac{2}{x}\)

x=1

Substitute this calculated values of x

y=-2(1)-4
y=-2-4
y=-6

So, the solution for the given system of equations is (x,y) = (1,−6).

The given system of equations i.e. y = −2x − 4 and y = −4x − 2 results in a solution value of x as 1 and y as −6 which was solved using basic mathematical operations.

Page 57 Exercise 27 Answer

In the question, a graph is given as

Also, four equations are given as

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 57 Exercise 27 Answer

a. y = \(\sqrt{x+5}\) − 3

b. y = \(\sqrt{x-3}\) + 5

c. y = \(\sqrt{x-5}\) + 3

d. y = \(\sqrt{x+3}\) + 5

It is required to state which of the given options is an equation for the transformation of the graph of the parent function y = √x shown in the given graph.

To solve this, find the origin of the given graph and find the equation of the curve using the shifted origin.

Find the origin of the curve from the given graph and find the equation of the curve using the shifted origin.

The given graph is

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 57 Exercise 27 Answer

From the graph origin of the curve is (−5,−3).

So, the equation of the curve is

⇒ \(\begin{aligned}
& y-(-3)=\sqrt{x-(-5)} \\
& y+3=\sqrt{x+5} \\
& y-(-3)=\sqrt{x-(-5)}
\end{aligned}\)

⇒ \(\begin{aligned}
& y+3=\sqrt{x+5} \\
& y=\sqrt{x+5}-3
\end{aligned}\)

So, option (A) is the correct option.

Option (A) y = \(\sqrt{x+5}\) – 3 is an equation for the transformation of the graph of the parent function y = √x shown in the given graph.

Page 57 Exercise 28 Answer

In the question, it is given that the formula for the volume of a cylinder in cubic feet is V = πr2h where r is the radius of the base in feet and h is the height in feet. Also, it is given that its volume is 1078πft3 and its height is 22 feet.

It is required to find the diameter of the cylinder.

To solve this, substitute the given volume and height in the equation V = πr2h and find r.

Then using this r, find the diameter d = 2r.

v=πr2h-1
v=1078π
h=22

Substitute the value in 1

v=πr2h
1078π=π.r2.22
Divide 22 on both sides

⇒ \(\begin{aligned}
& \frac{22 r^2}{22}=\frac{1078}{22} \\
& r^2=49
\end{aligned}\)

Square root on both sides

⇒ \(\begin{aligned}
\sqrt{r^2} & =\sqrt{49} \\
r & = \pm \sqrt{7^2} \\
r & = \pm 7
\end{aligned}\)

Since the radius is a length, it is positive

So,r=7

Diameter d=2r
d=2(7)
d=14

So, the diameter is 14ft.

By substituting the volume and height in the equation of volume, the radius of the cylinder is found as r = 7, and using this radius diameter is found as 14ft.

How To Solve Envision Algebra 1 Chapter 4 Questions

Page 57 Exercise 30 Answer

In the question, four pairs of points and four slopes are given as follows

(3, 1) and (5, -7) \(\frac{1}{4}\)

(10, 14) and (-2, 11) 4

(-11, 9) and (-12, 5) \(\frac{-1}{4}\)

(-2, 7) and (-10, 9) -4

It is required to match each pair of points to the slopes.

To match this, find the slope of each line using the formula m = \(\frac{y_2-y_1}{x_2-x_1}\) and match them according to the calculated slope.

Find the slope m1 of the line passing through (3,1) and (5,7)

⇒ \(\begin{aligned}
& m=\frac{y_2-y_1}{x_2-x_1} \\
& m_1=\frac{-7-1}{5-3} \\
& m_1=\frac{-8}{2} \Rightarrow m_1=-4
\end{aligned}\)

Find the slope m2 of the line passing through (10,14) and (-2,11)

⇒ \(\begin{aligned}
& m=\frac{y_2-y_1}{x_2-x_1} \\
& m=\frac{11-14}{-2-10} \\
& m_2=\frac{-3}{-12} \Rightarrow m_2=\frac{1}{4}
\end{aligned}\)

Find the slope m3 of the line passing through (-11,9) and (-12,5)

⇒  \(\begin{aligned}
& m=\frac{y_2-y_1}{x_2-x_1} \\
& m_3=\frac{5-9}{-12+11} \\
& m_3=\frac{-4}{-1} \Rightarrow m_3=4
\end{aligned}\)

Find the slope of the line passing through (-2,7) and (-10,9)

⇒ \(\begin{aligned}
& m=\frac{y_2-y_1}{x_2-x_1} \\
& m_4=\frac{9-7}{-10+2} \\
& m_4=\frac{2}{-8} \\
& m_4=\frac{-1}{4}
\end{aligned}\)

Match the points and the calculated slopes.

(3, 1) and (5, -7) -4

(10, 14) and (-2, 11) \(\frac{1}{4}\)

(-11, 9) and (-12, 5) 4

(-2, 7) and (-10, 9) \(\frac{-1}{4}\)

Envision Algebra 1 Assessment Readiness Workbook Student Edition Chapter 4 Page 58 Exercise 31 Answer

In the question, it is given that the ages of the members of a beach clean-up club are 16, 19, 22, 25, 31, 33, 38 and 42.

Also, it is given that a new member who is $19$ years old joins the club.

It is required to describe how the age of the new member will affect the mean, median, mode, and range of the ages of the club.

To solve this, first find the mean, median, mode, and range of the ages without the age of the new member. Then find the mean, median, mode, and range of the ages including the age of the new member. Compare the obtained answers in both cases to describe how the age of the new member will affect the mean, median, mode, and range.

Find the mean of the ages without the age of the new member.

Mean = \(\frac{16+19+22+25+31+33+38+42}{8}\)

Mean= \(\frac{226}{8}\)

Mean= 28.25

Find the median ages without age of new member

The middle numbers are 25 and 31

Median= \(\frac{25+31}{2}\)

Median= \(\frac{56}{2}\)

Median=28

Find the mode of the ages without the age of the new member.

Mode is the highest occurring number. Here every number occurs only once.

So, no mode exists.

Find the range of the ages without the age of the new member.

​Range = 42 − 16

= 26

Find the mean of the ages with the age of the new member.

mean = \(\frac{16+19+19+22+25+31+33+38+42}{9}\)

Mean= \(\frac{245}{9}\)

Mean= 27.22

Find the median of the ages with the age of the new member.

The middle number is 25.

Median = 25

Find the mode of the ages with the age of the new member.

​Mode = highest occurring number

= 19

Find the range of the ages with the age of the new member.

​Range = 42 − 16

= 26

The addition of new members with 19 years old will reduce the mean as 19 is small relative to the given data.

Median becomes a single number as there are an odd number of terms.

Mode is possible when the new member is added as there are two numbers of the same value.

The range will be the same as the highest and lowest numbers are the same.

Page 58 Exercise 32 Answer

In the question, an expression 8x5 − 26x4 + 6x3 is given.

It is required to find the factored form of 8x5 − 26x4 + 6x3 and to explain it.

To solve this, first take 2x3 common from the given expression. Then factorize the remaining function.

Given expression 8x5 − 26x4 + 6x3

Take 2x3 common from the expression

8×5-263=2×3(4×2-13x+3)

Factorise 4×2-13x+3

4×2-13x+3=4×2-12x-x+3
=4x(x-3)-1(x-3)

Take(x-3) common from the above equation
4x(x-3)-1(x-3)=(4x-1)(x-3)

take (x-3) common from the above equation

By taking 2x3 common and factorizing the remaining term, the factorization of 8x5 − 26x4 + 6x3 is found as 2x3(x−3)(4x−3).

Envision Algebra 1 Assessment Readiness Workbook Student Edition Chapter 4 Page 58 Exercise 33 Answer

In the question, it is given that the measure of angle A of an obtuse triangle is two times the measure of angle B, while the measure of angle C is 28° less than the measure of angle B.

It is required to explain what are the degree measures of the three angles.

To find this, take ∠A as 2∠B and ∠C as ∠B−28 in ∠A + ∠B + ∠C = 180° and find ∠B. Using the value of ∠B find the other two angles.

∠A+∠B+∠C=180°

Substitute ∠A=2∠B
∠C=∠B-28°

2∠B+∠B+∠B-28°=180°
4∠B=180°+28°
4∠B=208°

Divide 4 on both sides

⇒ \(\frac{4 \angle B}{4}=\frac{208^{\circ}}{4}\)

∠B=52°

Find ∠A by substituting the value of ∠B as 52°

∠A=2∠B
∠A=2(52)°
∠A=104°

Find ∠C by substituting the value of ∠B is 52°

∠C=∠B-28°
∠C=52°-28°
∠C= 24°

By taking ∠A as 2∠B and ∠C as ∠B − 28 in ∠A+∠B+∠C = 180°, the values of the three angles are found as

∠A=104°

∠B = 52°

∠C = 24°

Page 58 Exercise 34 Answer

In the question, a function f(x) = 9x2 + 15x − 6 is given.

It is required to find what are the zeros of the function f(x) = 9x2 + 15x − 6.

To find the zeros, put f(x) = 0 and solve using mathematical operations.

Put 9x2 + 5x − 6 = 0 and simplify to find the zeros.

Given function f(x)=9x2+15x-6

⇒ \(\begin{aligned}
& 9 x^2+15 x-6=0 \\
& 9 x^2+18 x-3 x-6=0 \\
& 9 x(x+2)-3(x+2)=0 \\
& (9 x-3)(x+2)=0
\end{aligned}\)

​Take 3 common from (9x-3)

(9x-3)(x+2)=0
3(3x-1)(x2)=0
(3x-1(x+2)=0

Here(3x-1) is o or (x+2) is o by the  property, if ab=0

Put(3x-1)=0 and find x

3x-1=0
3x=1
⇒ \(x=\frac{1}{3}\)

Put (x+2)=0 and find x
x+2=0
x=-2

By taking 9x2 + 15x − 6 = 0, the zeros of the function are found as x = \(\frac{1}{3}\) and x = −2.

Page 59 Exercise 35 Answer

In the question, it is given that Dakota has a combination of 18 dimes and quarters for a total of $2.70.

It is required to write a system of equations used to determine the number of each type of coin Dakota has and to determine how many coins of each type Dakota has.

To solve this, let the number of dimes as x and the number of quarters as y. The given condition is Dakota has a combination of 18 dimes and quarters. Convert the condition in terms of $. Then solve the two equations to find x.

Convert the given condition Dakota has a combination of $18$ dimes and quarters to equation form.

x+y=18
Put 1dime=$0.1
1quarter=$0.25 given condition

x+y=18
0.1+0.25y=2.7
x+2.5y=27

Solve the two equations x+y=18 and

x+2.5y=27
x.x+2.5y-y=27-18
1.5y=9
y=6

Substitute the value of y as 6

x+y=18
x+6=18
x=18-6
x=12

The system of equations used to determine the number of each type of coin Dakota has been x + y = 18.

The number of dimes is 12 and the number of quarters is 6.

Page 59 Exercise 36 Answer

In the question, a piecewise-defined function is given as

f(x) = \(\left\{\begin{array}{l}
4 x+7, \text { if } x<-2 \\
-x, \text { if }-2<x \leq 2 \\
1, \text { if } x>2
\end{array}\right.\)

It is required to graph the given piecewise function.

To plot this first take y = f(x) and find the coordinates by substituting different numbers in the range to the specified value of the function.

​Put x as -3 in the function y=4x+7

y=4(-3)+7
y=-12+7
y=-5

So, the coordinates are (-3,-5)

Put x as -4 in the function y=4x+7

y=4(-4)+7
y=-16+7
y=-9

So, the coordinates are (-4,9)

Put x as -1 in the function y=-x
y=-x
y=-(-1)
y=1

So, the coordinates are (-1,1)

Put x as 2 in the function y=x
y=-x
y=-2
so, the coordinates is (2,-2)

Put x as 3 in the function y = 1.

The coordinate is (3,1).

Put x as 4 in the function y = 1.

The coordinate is (4,1).

Plot the calculated point in the coordinate plane and draw the graph.

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 59 Exercise 36 Answer

The points are plotted on the coordinate plane as

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 59 Exercise 36 Answer

In the question, a function

f(x) = \(\left\{\begin{array}{l}
4 x+7, \text { if } x<-2 \\
-x, \text { if }-2<x \leq 2 \\
1, \text { if } x>2
\end{array}\right.\) is given.

It is required to find the domain and range of the function.

To solve the question, use the fact that the domain of all the polynomials is (−∞,∞).

Find the range for each interval separately and then take their union.

Find the domain of the function.

As it is given that

f(x) = \(\left\{\begin{array}{l}
4 x+7, \text { if } x<-2 \\
-x, \text { if }-2<x \leq 2 \\
1, \text { if } x>2
\end{array}\right.\)

Now, the function f(x) has a polynomial at every interval. So, the domain of the function is (−∞,∞).

Find the range of the function.

For x < −2, f(x) = 4x + 7

Also, ​

​f(−2) = 4(−2) + 7

= −1

Thus the range of the function is (−∞,−1) when x < −2.

For −2 < x ≤ 2, f(x) = −x

Thus the range of the function is [−2,2] for −2 < x ≤ 2.

Solve further to get the range of function f(x).

For x > 2, f(x) = 1.

So, the range of the function for the interval x > 2 is 1.

Now, the range of the function f(x),

​R = (−∞,−1)∪[−2,2)∪{1}

= (−∞,2)

Thus, the range of the function f(x) is (−∞,2).

Therefore, the domain of the function f(x) is (−∞,∞) and the range is (−∞,2) which were solved according to definitions of domain and range.

In the question, a function

f(x) = \(\left\{\begin{array}{l}
4 x+7, \text { if } x<-2 \\
-x, \text { if }-2<x \leq 2 \\
1, \text { if } x>2
\end{array}\right.\) is given.

It is required to find out on which interval function is increasing or decreasing.

To solve the question, for each interval find the first derivative of the function. If f′(x) < 0, then the f(x) is increasing on that interval. And if f′(x) > 0, then the f(x) decreases on that interval.

Find the intervals where function is increasing or decreasing.

For x < −2, f(x) = 4x + 7

​f′(x) = 4

f′(x) > 0

So, f(x) is decreasing on the interval (−∞,−2).

Solve further for more intervals.

For −2 < x ≤ 2, f(x) = −x

​f′(x) = −1

f′(x) < 0

So, f(x) is increasing on the interval [−2,2].

Solve further for more intervals.

For x > 2, f(x) = 1.

f′(x) = 0

Since f′(x) = 0 the function is constant in the interval (2,∞).

Therefore, function f(x) is decreasing on the interval (−∞,−2) and increasing on the interval [−2,2] which were solved by calculating the first derivative of the function at each interval.

Envision Algebra 1 Chapter 4 Step-By-Step Solutions

Envision Algebra 1 Assessment Readiness Workbook Student Edition Chapter 4 Page 60 Exercise 1 Answer

In the question, it is given that a person named Kayden is considering three different ways to rent movies and video games.

a. Rent movies and game disks for $2 each.

b. Unlimited games and movies to any device for $20 per month.

c. Rent movies and game disks for a $10 monthly fee plus $2.5 per disk.

It is required to write the functions that give the cost to rent x movies or disks per month for each plan, that is A(x), B(x), and C(x). Then graph the functions.

To solve the question, analyze the given data carefully and write functions accordingly for each plan. Then graph the functions.

Write functions for each plan that give the cost to rent x movies or disks per month for each plan.

For plan A, the cost function is A(x)=2x,

For plan B, the cost function is B(x)=20,

For plan C, cost function is C(x) = 10 + 2.5x

Plot the above functions on the graph.

A(x) = 2x

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 60 Exercise 1 Answer Image 1

C(x) = 10 + 2.5x

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 60 Exercise 1 Answer Image 2

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 60 Exercise 1 Answer Image 3

 

Thus, cost functions for

plan A is A(x) = 2x

plan B is B(x) = 20

plan C is C(x) = 10 + 2.5x,

which were solved by forming cost functions for the cost of x items.

The graph of the functions is

Envision Algebra 1 Assessment Chapter 4 Practice Test C Page 60 Exercise 1 Answer Image 3

In the question, it is given that a person named Kayden is considering three different ways to rent movies and video games.

Rent movies and game disks for $2 each.

Unlimited games and movies to any device for $20 per month.

Rent movies and game disks for a $10 monthly fee plus $2.5 per disk.

Also from the result of the previous part, the costs functions for

plan A is A(x) = 2x

plan B is B(x) = 20

plan C is C(x) = 10 + 2.5x

It is required to tell under what conditions Plan B is better than plan A if only cost is considered.

To solve the question, analyze the given data carefully. Now plan B is better than A if the cost of B is less than A. Solve the inequality and get the conditions using suitable mathematical operations.

Analyze the given data carefully.

For plan A, the cost function is A(x) = 2x,

For plan B, the cost function is B(x) = 20,

Now, the Cost of plan B is less than plan A when 20 < 2x

Divide by 2 on both sides.

\(\frac{20}{2}<\frac{2 x}{2}\)

x > 0

Now, if the number of disks is more than 10, plan A will be more costly than plan B where cost is constant.

Thus, when the number of disks is more than 10, plan B is better than plan A.

Thus, when the number of disks is more than 10, plan B is better than plan A which was solved by analyzing data and using appropriate mathematical operations.

In the question, it is given that a person named Kayden is considering three different ways to rent movies and video games.

Rent movies and game disks for $2 each.

Unlimited games and movies to any device for $20 per month.

Rent movies and game disks for $10 monthly fee plus $2.5 per disk.

Also from the result of the previous part, the cost functions for

plan A is A(x) = 2x

plan B is B(x) = 20

plan C is C(x) = 10 + 2.5x

It is required to tell under what conditions plan C is better than plan B, if only cost is considered.

To solve the question, analyze the given data carefully. Now plan C is better than B if the cost of C is less than B. Solve the inequality and get the conditions using suitable mathematical operations.

Analyze the given data carefully.

For plan B, the cost function is B(x) = 20,

For plan C, cost function is C(x) = 10 + 2.5x

The cost of plan C is less than plan B if 10 + 2.5x < 20

B(x)=20
c(x)=10+2.5x
10+2.5x<20
subtract 10 on both sides

10-10+2.5x<20-10
2.5x<10

Divide both sides by 2.5

\(\begin{gathered}
\frac{2.5 x}{2.5}<\frac{10}{2.5} \\
x<4
\end{gathered}\)

Now, if the number of disks is less than 4, plan C is less costly than plan B.

Thus, when the number of disks is less than 4, plan C is better than plan C which was solved by analysing data and using appropriate mathematical operations.

In the question, it is given that a person named Kayden is considering three different ways to rent movies and video games.

Rent movies and game disks for $2 each.

Unlimited games and movies to any device for $20 per month.

Rent movies and game disks for $10 monthly fee plus $2.5 per disk.

Also from result of previous part, costs functions for

plan A is A(x) = 2x

plan B is B(x) = 20

plan C is C(x) = 10 + 2.5x

It is required to show that Plan A is always more cost effective than Plan C.

To solve the question, analyse given data carefully. Compare costs of two plans by subtracting cost of plan A from plan C. If result is positive that means cost of plan A is always less than C.

Compare costs of plan C and plan A.

For plan A, cost function is A(x) = 2x,

For plan C, cost function is C(x) = 10 + 2.5x

Find their differences.

​C(x) − A(x) = 10 + 2.5x − 2x

= 10 + 0.5x

Now, since x is the number of disks, thus it cannot be negative. This means the difference is always positive.

Solve further for conclusion.

​C(x) − A(x) > 0

C(x) > A(x)

Thus, the cost of plan A is always less than plan C.

Therefore, it is shown that plan A is always cost-effective than plan C which was solved by comparing two costs.

Proof: A(x)=2x
C(x)=10+2.5x
C(x)-A(x)=10+2.5x-2x
=10+0.5x
C(x)-A(x)>0
C(x)>A(x)

Hence showed

In the question, it is given that a person named Kayden is considering three different ways to rent movies and video games.

Rent movies and game disks for $2 each.

Unlimited games and movies to any device for $20 per month.

Rent movies and game disks for $10 monthly fee plus $2.5 per disk.

Also from result of part(a), costs functions for

plan A is A(x) = 2x

plan B is B(x) = 20

plan C is C(x) = 10 + 2.5x

From part (b), plan B is more cost-effective than plan A when the number of disks is more than 10.

As a result of part (d), plan A is always more cost-effective than plan C.

It is required to recommend a plan to Kayden and justify the answer.

To solve the question, analyze the given data and results of previous steps carefully.

Since plan A is always more cost-effective than plan C. Plan B is more cost-effective than plan A when the number of disks is more than 10. It is more likely that he needs less than 10 disks. So, plan A is recommended.

Therefore, plan A) Rent movies and game disks for $2 each, is recommended as it is more likely that Kayden needs less than 10 disks per month.