Solve for x
x=2
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21x-21=21
Swap sides so that all variable terms are on the left hand side.
21x=21+21
Add 21 to both sides.
21x=42
Add 21 and 21 to get 42.
x=\frac{42}{21}
Divide both sides by 21.
x=2
Divide 42 by 21 to get 2.
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