Solve for x
x=2
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-x+21-2x=15
Subtract 2x from both sides.
-x-2x=15-21
Subtract 21 from both sides.
-x-2x=-6
Subtract 21 from 15 to get -6.
-3x=-6
Combine -x and -2x to get -3x.
x=\frac{-6}{-3}
Divide both sides by -3.
x=2
Divide -6 by -3 to get 2.
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