Solve for x
x=-9
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21+x\times 2=3
Swap sides so that all variable terms are on the left hand side.
x\times 2=3-21
Subtract 21 from both sides.
x\times 2=-18
Subtract 21 from 3 to get -18.
x=\frac{-18}{2}
Divide both sides by 2.
x=-9
Divide -18 by 2 to get -9.
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