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I know the answer, I just don't get how you factor the B into 2 variables.

I know the answer, I just don't get how you factor the B into 2 variables.-example-1

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10 votes

Answer:

Answer:

To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as
8x^(2) +ax+bx-3. To find a and b, set up a system to be solved.


a+b=-2


ab=8\left(-3\right)=-24

Since ab is negative, a and b have the opposite signs. Since a+b is negative, the negative number has greater absolute value than the positive. List all such integer pairs that give product -24.


1, -24\\ 2,-12\\ 3,-8\\ 4,-6

Calculate the sum for each pair.


1-24=-23\\ 2-12=-10\\ 3-8=-5\\ 4-6=-2

The solution is the pair that gives sum -2.


a=-6\\ b=4

Rewrite
8x^(2) -2x-3 as (8
x^(2) -6x)+(4x-3)


\left(8x^2-6x\right)+(4x-3)

Factor out 2x in 8x²-6x.


2x\left(4x-3\right)+4x-3

Factor out common term 4x-3 by using distributive property.


\left(4x-3\right)\left(2x+1\right)

To find equation solutions, solve 4x-3=0 and 2x+1=0


x=(3)/(4)\\ x=-(1)/(2)

I hope this helps you

:)

User Jack Miller
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