Use the elimination method:
-4x - 2y = -12
+4x + 8y = -12
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0 + 6y = -24
6y = -24
6y/6 = -24/6
y = -4
Plug in -4 for y in one of the equations
-4x - 2y = -12
-4x - 2(-4) = -12
-4x + 8 = -12
-4x + 8 (-8) = -12 (-8)
-4x = -20
-4x/-4 = -20/-4
x = 5
x = 5, y = -4
hope this helps