Solve for x
x=42
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2x-3=81
Square both sides of the equation.
2x-3-\left(-3\right)=81-\left(-3\right)
Add 3 to both sides of the equation.
2x=81-\left(-3\right)
Subtracting -3 from itself leaves 0.
2x=84
Subtract -3 from 81.
\frac{2x}{2}=\frac{84}{2}
Divide both sides by 2.
x=\frac{84}{2}
Dividing by 2 undoes the multiplication by 2.
x=42
Divide 84 by 2.
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