Solve for x
x=-6
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7x+9=9x+21
Use the distributive property to multiply 3 by 3x+7.
7x+9-9x=21
Subtract 9x from both sides.
-2x+9=21
Combine 7x and -9x to get -2x.
-2x=21-9
Subtract 9 from both sides.
-2x=12
Subtract 9 from 21 to get 12.
x=\frac{12}{-2}
Divide both sides by -2.
x=-6
Divide 12 by -2 to get -6.
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