Solve for x
x=-9
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4x+40=4
Square both sides of the equation.
4x+40-40=4-40
Subtract 40 from both sides of the equation.
4x=4-40
Subtracting 40 from itself leaves 0.
4x=-36
Subtract 40 from 4.
\frac{4x}{4}=-\frac{36}{4}
Divide both sides by 4.
x=-\frac{36}{4}
Dividing by 4 undoes the multiplication by 4.
x=-9
Divide -36 by 4.
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