Solve for x
x=3
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12x-15=21
Swap sides so that all variable terms are on the left hand side.
12x=21+15
Add 15 to both sides.
12x=36
Add 21 and 15 to get 36.
x=\frac{36}{12}
Divide both sides by 12.
x=3
Divide 36 by 12 to get 3.
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