Solve for x
x=15
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45-x-x=15
Subtract x from both sides.
45-2x=15
Combine -x and -x to get -2x.
-2x=15-45
Subtract 45 from both sides.
-2x=-30
Subtract 45 from 15 to get -30.
x=\frac{-30}{-2}
Divide both sides by -2.
x=15
Divide -30 by -2 to get 15.
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