Solve for x
x=84
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x-3=81
Square both sides of the equation.
x-3-\left(-3\right)=81-\left(-3\right)
Add 3 to both sides of the equation.
x=81-\left(-3\right)
Subtracting -3 from itself leaves 0.
x=84
Subtract -3 from 81.
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