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6x-3x^{2}=0
Subtract 3x^{2} from both sides.
x\left(6-3x\right)=0
Factor out x.
x=0 x=2
To find equation solutions, solve x=0 and 6-3x=0.
6x-3x^{2}=0
Subtract 3x^{2} from both sides.
-3x^{2}+6x=0
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
x=\frac{-6±\sqrt{6^{2}}}{2\left(-3\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -3 for a, 6 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-6±6}{2\left(-3\right)}
Take the square root of 6^{2}.
x=\frac{-6±6}{-6}
Multiply 2 times -3.
x=\frac{0}{-6}
Now solve the equation x=\frac{-6±6}{-6} when ± is plus. Add -6 to 6.
x=0
Divide 0 by -6.
x=-\frac{12}{-6}
Now solve the equation x=\frac{-6±6}{-6} when ± is minus. Subtract 6 from -6.
x=2
Divide -12 by -6.
x=0 x=2
The equation is now solved.
6x-3x^{2}=0
Subtract 3x^{2} from both sides.
-3x^{2}+6x=0
Quadratic equations such as this one can be solved by completing the square. In order to complete the square, the equation must first be in the form x^{2}+bx=c.
\frac{-3x^{2}+6x}{-3}=\frac{0}{-3}
Divide both sides by -3.
x^{2}+\frac{6}{-3}x=\frac{0}{-3}
Dividing by -3 undoes the multiplication by -3.
x^{2}-2x=\frac{0}{-3}
Divide 6 by -3.
x^{2}-2x=0
Divide 0 by -3.
x^{2}-2x+1=1
Divide -2, the coefficient of the x term, by 2 to get -1. Then add the square of -1 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
\left(x-1\right)^{2}=1
Factor x^{2}-2x+1. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.
\sqrt{\left(x-1\right)^{2}}=\sqrt{1}
Take the square root of both sides of the equation.
x-1=1 x-1=-1
Simplify.
x=2 x=0
Add 1 to both sides of the equation.