Solve for x
x=3
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15x-9-12x=0
Subtract 12x from both sides.
3x-9=0
Combine 15x and -12x to get 3x.
3x=9
Add 9 to both sides. Anything plus zero gives itself.
x=\frac{9}{3}
Divide both sides by 3.
x=3
Divide 9 by 3 to get 3.
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