Math
Solve for both systems 4x + y = 18 and 4x + 5y = 42
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Asked by
AnneS2
Last updated by
anonymous
4x + y = 18
4x-4x + y = 18-4x
y = 18-4x
4x + 5y = 42
4x + 5(18-4x) = 42
4x + 5(18) (5)(-4x) = 42
4x+90-20x=42
90-16x=42
90-16x-90=42-90
-16x=-48
-16x/-16=-48/-16
x=3
y = 18-4x
y = 18-4(3)
y = 18-12=6