Solve for x
x=-9
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3x+18-x=0
Subtract x from both sides.
2x+18=0
Combine 3x and -x to get 2x.
2x=-18
Subtract 18 from both sides. Anything subtracted from zero gives its negation.
x=\frac{-18}{2}
Divide both sides by 2.
x=-9
Divide -18 by 2 to get -9.
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Limits
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