4x-5y=-12 dan 2x+3y=18

4x - 5y = -12----- × 2
2x + 3y = 18----- × 4
jadi

8x - 10y = - 24
8x + 12y = 72
--------------------- -
2y = -96
y = -48

sub pada pers 1

4x - 5y = -12
4x - 5.(-48) = -12
4x - (240) = -12
4x = -12 + 240
4x = 228
x = 57

maaf kalo salah