Solve for x
x=-15
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-x+3=18
Square both sides of the equation.
-x+3-3=18-3
Subtract 3 from both sides of the equation.
-x=18-3
Subtracting 3 from itself leaves 0.
-x=15
Subtract 3 from 18.
\frac{-x}{-1}=\frac{15}{-1}
Divide both sides by -1.
x=\frac{15}{-1}
Dividing by -1 undoes the multiplication by -1.
x=-15
Divide 15 by -1.
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