Solve for b
b=30
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2b+4=64
Square both sides of the equation.
2b+4-4=64-4
Subtract 4 from both sides of the equation.
2b=64-4
Subtracting 4 from itself leaves 0.
2b=60
Subtract 4 from 64.
\frac{2b}{2}=\frac{60}{2}
Divide both sides by 2.
b=\frac{60}{2}
Dividing by 2 undoes the multiplication by 2.
b=30
Divide 60 by 2.
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