## Precalculus (10th Edition)

$\{(3,-1)\}$
We are given the system of equations: $\begin{cases} -2x+y=-7\\ 4x+3y=9 \end{cases}$ Use the substitution method: $\begin{cases} y=2x-7\\ 4x+3y=9 \end{cases}$ Substitute the expression of $y$ from the first equation into the second to find $x$: $4x+3(2x-7)=9$ $4x+6x-21=9$ $10x=30$ $x=3$ Determine $y$: $y=2(3)-7$ $y=-1$ The solution set is: $\{(3,-1)\}$