Solve for x
x=-8
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3x+31-x=15
Subtract x from both sides.
2x+31=15
Combine 3x and -x to get 2x.
2x=15-31
Subtract 31 from both sides.
2x=-16
Subtract 31 from 15 to get -16.
x=\frac{-16}{2}
Divide both sides by 2.
x=-8
Divide -16 by 2 to get -8.
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