Solve for x
x=12
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9x-21-6x=15
Subtract 6x from both sides.
3x-21=15
Combine 9x and -6x to get 3x.
3x=15+21
Add 21 to both sides.
3x=36
Add 15 and 21 to get 36.
x=\frac{36}{3}
Divide both sides by 3.
x=12
Divide 36 by 3 to get 12.
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