Answer:
X= 9
Y = -6
Explanation:
first of all setting up the equation and solve it like a system of linear equations
5x+4y=21
-3x+2y=-39
then multiply -2 on the entire second equation
5x+4y = 21
6x-4y= 78
then eliminate the 4ys and you get
11x = 99
x = 9
lastly subsititue the 9 back into one of the original equations
5(9) + 4y =21
45 + 4y = 21
4y = -24
y = -6