Answer
$(3,-6)$
Work Step by Step
Eliminate y,
$\left\{\begin{array}{lllll}
5x & -y & =21 & /\times 3 & \\
2x & +3y & =-12 & & ...add
\end{array}\right.$
$15x+2x=63-12$
$17x=51$
$x=3$
Back - substitute:
$5x-\mathrm{y}=21$
$5(3)-\mathrm{y}=21$
$-y=21-15$
$y=-6$
Solution: $(3,-6)$
Graphing, use x- and y-intercepts
$\left[\begin{array}{lll}
& & \\
& (y=0) & (x=0)\\
5x-\mathrm{y}=21 & 5x=21 & -y=21\\
& x=4.2 & y=-21\\
& (4.2,0) & (0,-21)\\
& & \\
2x+3y=-12 & 2x=-12 & 3y=-12\\
& x=-6 & y=-4\\
& (-6,0) & (0,-4)
\end{array}\right]$
