Precalculus (6th Edition) Blitzer

$(-2,3)$
Step 1. Use the substitution method with $y=2x+7$ and plug-in the first equation: $2x-3(2x+7)=-13$ which gives $2x-6x-21=-13$ and $4x=-8$ then $x=-2$ Step 2. Back-substitute $x=-2$ in to the second equation; we have $y=2(-2)+7=3$ Step 3. We find the solutions as $(-2,3)$