Answer:
(10,-3)
Step-by-step explanation:
3x + y = 27
–3x + 4y = –42
Add the two equations together to eliminate x
3x + y = 27
–3x + 4y = –42
---------------------------
5y = -15
Divide each side by 5
5y/5 = -15/5
y = -3
Now we can find x
3x+y = 27
Substituting y=-3
3x -3 = 27
3x-3+3 =27+3
3x= 30
Divide by 3
3x/3 = 30/3
x = 10
(10,-3)