Answer
$2b(a+3)(3a-10)$
Work Step by Step
$ 6a^{2}b-2ab-60b\qquad$...factor out the common term, $2b$.
$=2b(3a^{2}-a-30)$
... Searching for two factors of $ac=-90$ whose sum is $b=-1,$
we find$\qquad 9$ and $-10.$
Rewrite the middle term and factor in pairs:
$=2b(3a^{2}+9a-10a-30)=$
$=2b[3a(a+3)-10(a+3)]$
= $2b(a+3)(3a-10)$