Solve for x
x=-7
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4x-9-7x=12
Subtract 7x from both sides.
-3x-9=12
Combine 4x and -7x to get -3x.
-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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