Answer
$\{(1,-4)\}$
Work Step by Step
We are given the system of equations:
$\begin{cases}
x+2y=-7\\
x+y=-3
\end{cases}$
Use the elimination method. Multiply the second equation by -1 and add it to the first equation to eliminate $x$ and determine $y$:
$\begin{cases}
x+2y=-7\\
-x-y=-(-3)
\end{cases}$
$x+2y-x-y=-7+3$
$y=-4$
Determine $x$:
$x+y=-3$
$x-4=-3$
$x=1$
The solution set of the system is:
$\{(1,-4)\}$
