Answer
$\{(2,3)\}$
Work Step by Step
1. The least work in creating opposite coefficients is to
multiply the second equation by ($-4)$ ,
which will lead to eliminating x
$\left\{\begin{array}{lll}
12x & -5y & =9\\
-12x & +32y & =72
\end{array}\right.$
2. ... add the equations and solve
$27y=81\qquad/\div 27$
$y=3$
3. Back-substitute into one of the initial equations
$3x-8y=-18$
$3x-8(3)=-18$
$3x-24=-18\qquad/+24$
$3x=6\qquad/\div 3$
$x=2$
4. Write the solution as an ordered pair.
Solution set: $\{(2,3)\}$
