Pearson Algebra 2 Common Core, 2011
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Pearson Algebra 2 Common Core, 2011 View details
Chapter Review
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Exercise 26 Page 349

How can factoring out the GCF help you apply the Zero Product Property?

0, - 1 ± sqrt(37)/2

Practice makes perfect

To solve the given equation by factoring, we will start by writing all the terms on the left-hand side. Then, we will factor out the GCF.

3x^3+3x^2=27x
3x^3+3x^2-27x=0
3x( x^2+x-9 ) =0

We have rewritten the left-hand side as a product of two factors. Now, we will apply the Zero Product Property to solve the equation.

3x( x^2+x-9 ) =0
lc3x=0 & (I) x^2+x-9=0 & (II)
lx=0 x^2+x-9=0

From Equation (I), we found that one solution is x=0. To find other solutions, we will solve Equation (II). Note that this is a quadratic equation. Thus, we will use the Quadratic Formula. ax^2+bx+c=0 ⇔ x=- b±sqrt(b^2-4ac)/2a To do so, we first need to identify a, b, and c. x^2+x-9=0 ⇔ 1x^2+ 1x+( - 9)=0 We see that a= 1, b= 1, and c= - 9. Let's substitute these values into the formula and solve for x.

x=- b±sqrt(b^2-4ac)/2a
x=- 1±sqrt(1^2-4( 1)( - 9))/2( 1)
â–¼
Solve for x
x=- 1±sqrt(1-4(1)(- 9))/2(1)
x=- 1±sqrt(1-4(- 9))/2(1)
x=- 1±sqrt(1+36)/2(1)
x=- 1±sqrt(37)/2(1)
x=- 1±sqrt(37)/2

These solutions to the quadratic equation are also solutions for the given equation. Solutions x=0, x=- 1 ± sqrt(37)/2