Solve for x
x=8
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2x+21-4x=5
Subtract 4x from both sides.
-2x+21=5
Combine 2x and -4x to get -2x.
-2x=5-21
Subtract 21 from both sides.
-2x=-16
Subtract 21 from 5 to get -16.
x=\frac{-16}{-2}
Divide both sides by -2.
x=8
Divide -16 by -2 to get 8.
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