Solve for a
a=-4
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-2a+8=16
Square both sides of the equation.
-2a+8-8=16-8
Subtract 8 from both sides of the equation.
-2a=16-8
Subtracting 8 from itself leaves 0.
-2a=8
Subtract 8 from 16.
\frac{-2a}{-2}=\frac{8}{-2}
Divide both sides by -2.
a=\frac{8}{-2}
Dividing by -2 undoes the multiplication by -2.
a=-4
Divide 8 by -2.
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