2x - y = -7 4x - y = -4
2x = y - 7 4x = y - 4
y = 2x + 7 y = 4x + 4
4x + 4 = 2x + 7
4x - 2x = 7 - 4
2x = 3
x = 3/2
y = 2(3/2) +7
y = 3 + 7 = 10
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2(3/2) - 10 =-7 4(3/2) - 10 = -4
3 - 10 = -7 6 - 10 = -4