3x+3y=-18 (<--- divide this by 3)
-9x+y=64
so its x+y=-18
-9+y=64
then you get rid of y by minusing the two equations so its 10x =-70
then -70 devided by 10 = x which = -7
to find y all you have to do is substitute x with -7 into one of those equations
Done 'KC'