Solve for x
x=4
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3x+4=16
Square both sides of the equation.
3x+4-4=16-4
Subtract 4 from both sides of the equation.
3x=16-4
Subtracting 4 from itself leaves 0.
3x=12
Subtract 4 from 16.
\frac{3x}{3}=\frac{12}{3}
Divide both sides by 3.
x=\frac{12}{3}
Dividing by 3 undoes the multiplication by 3.
x=4
Divide 12 by 3.
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