Answer
$2 (3x+4)(x-2) $
Work Step by Step
Factoring by grouping:
1. Multiply the leading coefficient, a, and the constant, c.
2. Find the factors of ac whose sum is b.
3. Rewrite the middle term, bx, as a sum or difference using the factors from step 2.
4. Factor by grouping
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$9x^{2}-6x-24 =...$
Always start by searching for a GCF ... ($GCF=3$).
$=3(3x^{2}-2x-8)=...$
Now, the parentheses:
1. $\quad ac=-24 \qquad $
2. $\quad$sum = $-2\quad$... factors: $-6$ and $+4$
3. $\quad (3x^{2}-2x-8) = (3x^{2}-6\mathrm{x})+(4x-8)$
4. $\quad$... $= 3x(x-2)+(4)(x-2) = (3x+4)(x-2) $
$...$= $2 (3x+4)(x-2) $
