Answer
$-x+12y$
Work Step by Step
Using $a(b+c)=ab+ac$ (or the Distributive Property), and then combining like terms, the given expression, $
6x+5y-7(x-y)
,$ simplifies to
\begin{array}{l}\require{cancel}
6x+5y-7x+7y
\\\\=
-x+12y
.\end{array}