Chapter 6
Elementary and Intermediate Algebra · 675 exercises
Problem 8
Use multiplication to determine if each factorization is correct. a. \(9 y^{2}-12 y+4=(3 y-2)^{2}\) b. \(n^{2}-16=(n+8)(n-8)\)
3 step solution
Problem 8
What step should be performed first to solve \(x^{2}-6 x-16=0 ?\)
4 step solution
Problem 8
\((x-2)\left(x^{2}+2 x+4\right)\) is the factorization of what binomial?
6 step solution
Problem 8
Check to determine whether \((3 t-1)(5 t-6)\) is the correct factorization of \(15 t^{2}-19 t+6\).
4 step solution
Problem 8
Check to determine whether each factorization is correct. a. \(9 y^{3}+5 y^{2}-15 y=3 y\left(3 y^{2}+2 y-5\right)\) b. \(3 s^{3}+2 s^{2}+6 s+4=(3 s+2)\left(s^{2}+2\right)\)
2 step solution
Problem 9
For each of the following polynomials, which factoring method would you use first? $$ m^{2}+3 m n+2 n^{2} $$
4 step solution
Problem 9
What step (or steps) should be performed first before factoring is used to solve each equation? a. \(x^{2}+7 x=-6\) b. \(x(x+7)=3\)
3 step solution
Problem 9
Check to determine whether each factorization is correct. a. \(x^{2}-x-20=(x+5)(x-4)\) b. \(4 a^{2}+12 a-16=4(a-1)(a+4)\)
2 step solution
Problem 9
Use multiplication to determine if the factorization is correct. $$ b^{3}+27=(b+3)\left(b^{2}+3 b+9\right) $$
6 step solution
Problem 9
A trinomial has been partially factored. Complete each statement that describes the type of integers we should consider for the blanks. \(5 y^{2}-13 y+6=(5 y \square)(y \square)\) since the last term of the trinomial is positive and the middle term is negative, the integers must be _____ factors of 6.
4 step solution
Problem 9
Fill in the blanks to complete each factorization. $$ \begin{aligned} 2 x^{2}+6 x &=2 x \cdot x+2 x \cdot 3 \\ &= ( ) \end{aligned} $$
3 step solution
Problem 10
For each of the following polynomials, which factoring method would you use first? $$ 16-25 z^{2} $$
4 step solution
Problem 10
A ball is thrown into the air. Its height \(h\) in feet, \(t\) seconds after being released, is given by the formula \(h=-16 t^{2}+24 t+6\) When the ball hits the ground, what is the value of \(h ?\)
6 step solution
Problem 10
Check to determine whether the given number is a solution of the given quadratic equation. a. \(x^{2}-4 x=0 ; 4\) b. \(x^{2}-2 x-7=0 ;-2\)
5 step solution
Problem 10
Find two integers whose a. product is 10 and whose sum is 7 . b. product is 8 and whose sum is \(-6\) c. product is \(-6\) and whose sum is 1 d. product is \(-9\) and whose sum is \(-8 .\)
8 step solution
Problem 10
The factorization of \(y^{3}+27\) is \((y+3)\left(y^{2}-3 y+9\right) .\) Is this factored completely, or does \(y^{2}-3 y+9\) factor further?
5 step solution
Problem 10
A trinomial has been partially factored. Complete each statement that describes the type of integers we should consider for the blanks. \(5 y^{2}+13 y+6=(5 y \square)(y \square)\) since the last term of the trinomial is positive and the middle term is positive, the integers must be _____ factors of 6.
4 step solution
Problem 10
Fill in the blanks to complete each factorization. \(3 t^{3}-t^{2}+15 t-5=t^{2}(3 t-1)+5(3 t-1)\) = ( ) ( )
3 step solution
Problem 11
Complete each solution to solve the equation. $$ \begin{array}{rlrl} {(x-1)(x+7)} & {=0} & {} & {} \\ {x-1} & {\text { or }} & {} & {=0} \\ {x=1} & {} & {} & {x} & {=} \end{array} $$
4 step solution
Problem 11
Complete each factorization. $$ x^{2}-64=(x \quad 8)(x\quad 8) $$
5 step solution
Problem 11
Consider a trinomial of the form \(x^{2}+b x+c\) a. If \(c\) is positive, what can be said about the two integers that should be chosen for the factorization? b. If \(c\) is negative, what can be said about the two integers that should be chosen for the factorization?
3 step solution
Problem 11
A trinomial has been partially factored. Complete each statement that describes the type of integers we should consider for the blanks. \(5 y^{2}-7 y-6=(5 y \square)(y \square)\) since the last term of the trinomial is negative, the signs of the integers will be _____.
3 step solution
Problem 11
Consider the polynomial \(2 k-8+h k-4 h\) a. How many terms does the polynomial have? b. Is there a common factor of all the terms, other than \(1 ?\) c. What is the GCF of the first two terms and what is the GCF of the last two terms?
5 step solution
Problem 12
Use multiplication to determine whether the factorization is correct. $$ 5 c^{3} d^{2}-40 c^{2} d^{3}+35 c d^{4}=5 c d^{2}(c-7 d)(c-d) $$
4 step solution
Problem 12
Complete the solution to solve the equation. Fill in the blanks. a. Consecutive integers can be represented by \(x\) and___________ b. Consecutive odd integers can be represented by \(x\) and_________ c. Consecutive even integers can be represented by \(x\) and____________
3 step solution
Problem 12
Complete each factorization. \(16 t^{2}-49=(4 t+\quad)(4 t-\quad)\)
4 step solution
Problem 12
Fill in each blank to explain how to factor \(x^{2}+7 x+10\) by grouping. We express the middle term, \(7 x,\) as the sum of _____ terms: $$x^{2}+7 x+10=x^{2}+\square x+\square x+10$$
3 step solution
Problem 12
A trinomial has been partially factored. Complete each statement that describes the type of integers we should consider for the blanks. \(5 y^{2}+7 y-6=(5 y \square)(y \square)\) since the last term of the trinomial is negative, the signs of the integers will be_____.
3 step solution
Problem 12
What is the first step in factoring \(8 y^{2}-16 y z-6 y+12 z ?\)
2 step solution
Problem 13
Complete each factorization. $$ \begin{aligned} 6 m^{3}-28 m^{2}+16 m &=2 m\left(3 m^{2}-\square+8\right) \\ &=2 m(3 m-2)(\square-4) \end{aligned} $$
5 step solution
Problem 13
Geometry Problems Flags. The length of the flag of Australia is twice as long as the width. Find the dimensions of an Australian flag if its area is \(18 \mathrm{ft}^{2}\) (IMAGE CANNOT COPY)
5 step solution
Problem 13
Complete each solution to solve the equation. $$ \begin{aligned} &\begin{array}{r} {p^{2}-p-6=0} \\ {(-3)(p+2)=0} \end{array}\\\ &=0 \quad \text { or } \quad p+2=\\\ &p=\ \quad | \quad p= \end{aligned} $$
5 step solution
Problem 13
Determine whether each of the following is a perfect-square trinomial. $$ x^{2}+18 x+81 $$
4 step solution
Problem 13
Complete each factorization. $$ b^{3}+27=(\quad)\left(b^{2}-3 b+9\right) $$
4 step solution
Problem 14
Complete each factorization. $$ \begin{aligned} 2 a^{3}+& 3 a^{2}-2 a-3 \\ &=\square(2 a+3)-1(\square+3) \\ &=(\square)\left(a^{2}-1\right) \\ &=(2 a+3)(a+1)(\square) \end{aligned} $$
6 step solution
Problem 14
To factor a trinomial by grouping, a student made a table and circled the correct pair of integers, as shown. Enter the correct coefficients for the first stage in the factorization process. Key number \(=16\) $$\begin{array}{|c|c|}\hline \text { Factors } & {\text { Sum }} \\\\\hline 1 \cdot 16 & {17} \\\\\hline(2 \cdot 8& {10} \\\\\hline 4 \cdot 4 & {8} \\\\\hline\end{array}$$ $$x^{2}+\quad x+\quad x+16$$
6 step solution
Problem 14
Geometry Problems Billiards. Pool tables are rectangular, and their length is twice the width. Find the dimensions of a pool table if it occupies \(50 \mathrm{ft}^{2}\) of floor space.
6 step solution
Problem 14
Determine whether each of the following is a perfect-square trinomial. $$ x^{2}+14 x+49 $$
4 step solution
Problem 14
Complete each factorization. $$ z^{3}-125=(z-5)(\quad+5 z+\quad) $$
3 step solution
Problem 14
Complete each factorization. $$ 10 a^{4}-15 a^{3}=5 a \quad(2 a-3) $$
3 step solution
Problem 15
Factor. See Example 1 or Objective 1 $$x^{2}+3 x+2$$
4 step solution
Problem 15
Geometry Problems X-Rays. A rectangular-shaped x-ray film has an area of 80 square inches. The length is 2 inches longer than the width. Find its width and length. (IMAGE CANNOT COPY)
8 step solution
Problem 15
Solve each equation. $$ (x-3)(x-2)=0 $$
3 step solution
Problem 15
Determine whether each of the following is a perfect-square trinomial. $$ y^{2}+2 y+4 $$
4 step solution
Problem 15
Give an example of each type of expression. a. the sum of two cubes b. the cube of a sum
4 step solution
Problem 15
a. Suppose we wish to factor \(12 b^{2}+20 b-9\) by grouping. Identify \(a, b,\) and \(c\) b. What is the key number, \(a c ?\)
3 step solution
Problem 16
Factor. See Example 1 or Objective 1 $$ y^{2}+4 y+3 $$
6 step solution
Problem 16
Solve each equation. $$ (x+2)(x+3)=0 $$
5 step solution
Problem 16
Determine whether each of the following is a perfect-square trinomial. $$ y^{2}+4 y+16 $$
4 step solution
Problem 16
Give an example of each type of expression. a. the difference of two cubes b. the cube of a difference
4 step solution