Solve for x
x=18
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7x+15=9x-21
Use the distributive property to multiply 3 by 3x-7.
7x+15-9x=-21
Subtract 9x from both sides.
-2x+15=-21
Combine 7x and -9x to get -2x.
-2x=-21-15
Subtract 15 from both sides.
-2x=-36
Subtract 15 from -21 to get -36.
x=\frac{-36}{-2}
Divide both sides by -2.
x=18
Divide -36 by -2 to get 18.
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