Solve for x
x=20
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80-x-x=40
Subtract x from both sides.
80-2x=40
Combine -x and -x to get -2x.
-2x=40-80
Subtract 80 from both sides.
-2x=-40
Subtract 80 from 40 to get -40.
x=\frac{-40}{-2}
Divide both sides by -2.
x=20
Divide -40 by -2 to get 20.
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