Solve for x
x=6
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3x+15+8x=81
Add 8x to both sides.
11x+15=81
Combine 3x and 8x to get 11x.
11x=81-15
Subtract 15 from both sides.
11x=66
Subtract 15 from 81 to get 66.
x=\frac{66}{11}
Divide both sides by 11.
x=6
Divide 66 by 11 to get 6.
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