Answer
One common solution $\Rightarrow$ $(4,-1)$
Work Step by Step
We use the addition method below:
We add the 2 equations:
$3x+5y=7$
$2x-7y=15$
Multiply both sides of the 1st equation by $2$ to cancel $x$.
Multiply both sides of the 2nd equation by $-3$ to cancel $x$.
We get:
$+6x+10y=14$
$\underline{-6x+21y=-45}$
$31y=-31$
Solve for $y$ and simplify:
$y=\frac{-31}{31}=-1$
Substitute into any of the 2 equations and solve for $x$:
$3x+5y=7$
$3x+5(-1)=7$
$3x-5=7$
$3x=7+5$
$3x=12$
$x=\frac{12}{3}$
$x=4$
