Answer
$5(x+2)(x-3)$
Work Step by Step
$ 5x^{2}-5x-30\qquad$...factor out the GCF, $5$.
$=5(x^{2}-x-6)$
Two factors of $ac=-6$, whose sum is $b=-1$
are $+2$ and $-3$.
Rewrite $-x$ as $2x-3x$ and factor in pairs.
$5(x^{2}-x-6)$
$=5(x^{2}+2x-3x-6)$
$=5[x(x+2)-3(x+2)]$
$=5(x+2)(x-3)$