Answer:
(-2 , 8)
Explanation:
We substitute y by -4x in the second equation of the system:
-4x = 4x + 16
⇔ -8x = 16
⇔ x = 16/(-8)
⇔ x = -2
Now ,we substitute x by -2 in the first equation of the system:
y = -4 × (-2) = 8
then
the solution of the system is {(x = -2 , y = 8)}