Solve for x
x=20
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x+80-x\times 4=20
Subtract x\times 4 from both sides.
-3x+80=20
Combine x and -x\times 4 to get -3x.
-3x=20-80
Subtract 80 from both sides.
-3x=-60
Subtract 80 from 20 to get -60.
x=\frac{-60}{-3}
Divide both sides by -3.
x=20
Divide -60 by -3 to get 20.
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