Solve for x
x=18
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3x+13+x=85
Combine 2x and x to get 3x.
4x+13=85
Combine 3x and x to get 4x.
4x=85-13
Subtract 13 from both sides.
4x=72
Subtract 13 from 85 to get 72.
x=\frac{72}{4}
Divide both sides by 4.
x=18
Divide 72 by 4 to get 18.
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