Solve for x
x=57
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3x+3x+45=387
Use the distributive property to multiply 3 by x+15.
6x+45=387
Combine 3x and 3x to get 6x.
6x=387-45
Subtract 45 from both sides.
6x=342
Subtract 45 from 387 to get 342.
x=\frac{342}{6}
Divide both sides by 6.
x=57
Divide 342 by 6 to get 57.
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