Solve for x
x=15
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x+3=3\left(x-9\right)
Add -12 and 3 to get -9.
x+3=3x-27
Use the distributive property to multiply 3 by x-9.
x+3-3x=-27
Subtract 3x from both sides.
-2x+3=-27
Combine x and -3x to get -2x.
-2x=-27-3
Subtract 3 from both sides.
-2x=-30
Subtract 3 from -27 to get -30.
x=\frac{-30}{-2}
Divide both sides by -2.
x=15
Divide -30 by -2 to get 15.
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