Solve for x
x = \frac{13}{3} = 4\frac{1}{3} \approx 4.333333333
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3x-9=4
Square both sides of the equation.
3x-9-\left(-9\right)=4-\left(-9\right)
Add 9 to both sides of the equation.
3x=4-\left(-9\right)
Subtracting -9 from itself leaves 0.
3x=13
Subtract -9 from 4.
\frac{3x}{3}=\frac{13}{3}
Divide both sides by 3.
x=\frac{13}{3}
Dividing by 3 undoes the multiplication by 3.
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