Solve for x
x=7
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12=3x-9
Combine 5x and -2x to get 3x.
3x-9=12
Swap sides so that all variable terms are on the left hand side.
3x=12+9
Add 9 to both sides.
3x=21
Add 12 and 9 to get 21.
x=\frac{21}{3}
Divide both sides by 3.
x=7
Divide 21 by 3 to get 7.
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