Answer
$ (x+7)(5x-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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Always start by searching for a GCF ... (there are none other than 1).
1. $\quad ac=-70$
2. $\quad$sum = $+33 \quad$... factors: $+35$ and $-2$
3. $\quad 5x^{2}+33x-14=(5x^{2}+35x)+( -2x-14)$
4. $\quad$... $=5x(x+7) +(-2)(x+7) =(x+7)(5x-2)$
Check by FOIL
$F:\quad 5x^{2}$
$O:\quad -2x$
$I:\quad +35x$
$L:\quad -14$
$ (x+7)(5x-2) $ = $5x^{2}+33x-14$
