Solve for x
x=12
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3x+15-6x=-21
Subtract 6x from both sides.
-3x+15=-21
Combine 3x and -6x to get -3x.
-3x=-21-15
Subtract 15 from both sides.
-3x=-36
Subtract 15 from -21 to get -36.
x=\frac{-36}{-3}
Divide both sides by -3.
x=12
Divide -36 by -3 to get 12.
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