Solve for x
x=-4
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-2x+1=9
Square both sides of the equation.
-2x+1-1=9-1
Subtract 1 from both sides of the equation.
-2x=9-1
Subtracting 1 from itself leaves 0.
-2x=8
Subtract 1 from 9.
\frac{-2x}{-2}=\frac{8}{-2}
Divide both sides by -2.
x=\frac{8}{-2}
Dividing by -2 undoes the multiplication by -2.
x=-4
Divide 8 by -2.
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