Answer
$(x+5y)(x-6y)$
Work Step by Step
The given expression, $
x^2-xy-30y^2
,$ has $c=
-30
$ and $b=
-1
.$
The possible factors of $c$ are $
\{ 1,-30 \}
,\{ 2,-15 \}
,\{ 3,-10 \}
,\{ 5,-6 \}
,\{ -1,30 \}
,\{ -2,15 \}
,\{ -3,10 \}
,\{ -5,6 \}$. Among these factors, the pair whose sum is equal to $b$ is $\{
5,-6
\}.$ Hence, the factored form is
\begin{array}{l}\require{cancel}
(x+5y)(x-6y)
.\end{array}