Step-by-step explanation:
10x - 10y = -20
-10y = -20 - 10x
y = -20/-10 - 10x/-10
y = 2 + x
-10x + 4y = -16
-10x + 4(2 + x) = -16
-10x + 8 + 4x = -16
-6x = -24
x = -24/-6
x = 4
y = 2 + 4
y = 6
Solution = (4,6)
