Solve for x
x=7
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1-12x+9x=-20
Add 9x to both sides.
1-3x=-20
Combine -12x and 9x to get -3x.
-3x=-20-1
Subtract 1 from both sides.
-3x=-21
Subtract 1 from -20 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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