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3x=6\times 1x\left(\frac{1}{3}x-2\right)
Multiply both sides of the equation by 12, the least common multiple of 4,2,3.
3x=6x\left(\frac{1}{3}x-2\right)
Multiply 6 and 1 to get 6.
3x=6x\times \frac{1}{3}x-12x
Use the distributive property to multiply 6x by \frac{1}{3}x-2.
3x=6x^{2}\times \frac{1}{3}-12x
Multiply x and x to get x^{2}.
3x=\frac{6}{3}x^{2}-12x
Multiply 6 and \frac{1}{3} to get \frac{6}{3}.
3x=2x^{2}-12x
Divide 6 by 3 to get 2.
3x-2x^{2}=-12x
Subtract 2x^{2} from both sides.
3x-2x^{2}+12x=0
Add 12x to both sides.
15x-2x^{2}=0
Combine 3x and 12x to get 15x.
x\left(15-2x\right)=0
Factor out x.
x=0 x=\frac{15}{2}
To find equation solutions, solve x=0 and 15-2x=0.
3x=6\times 1x\left(\frac{1}{3}x-2\right)
Multiply both sides of the equation by 12, the least common multiple of 4,2,3.
3x=6x\left(\frac{1}{3}x-2\right)
Multiply 6 and 1 to get 6.
3x=6x\times \frac{1}{3}x-12x
Use the distributive property to multiply 6x by \frac{1}{3}x-2.
3x=6x^{2}\times \frac{1}{3}-12x
Multiply x and x to get x^{2}.
3x=\frac{6}{3}x^{2}-12x
Multiply 6 and \frac{1}{3} to get \frac{6}{3}.
3x=2x^{2}-12x
Divide 6 by 3 to get 2.
3x-2x^{2}=-12x
Subtract 2x^{2} from both sides.
3x-2x^{2}+12x=0
Add 12x to both sides.
15x-2x^{2}=0
Combine 3x and 12x to get 15x.
-2x^{2}+15x=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{-15±\sqrt{15^{2}}}{2\left(-2\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -2 for a, 15 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-15±15}{2\left(-2\right)}
Take the square root of 15^{2}.
x=\frac{-15±15}{-4}
Multiply 2 times -2.
x=\frac{0}{-4}
Now solve the equation x=\frac{-15±15}{-4} when ± is plus. Add -15 to 15.
x=0
Divide 0 by -4.
x=-\frac{30}{-4}
Now solve the equation x=\frac{-15±15}{-4} when ± is minus. Subtract 15 from -15.
x=\frac{15}{2}
Reduce the fraction \frac{-30}{-4} to lowest terms by extracting and canceling out 2.
x=0 x=\frac{15}{2}
The equation is now solved.
3x=6\times 1x\left(\frac{1}{3}x-2\right)
Multiply both sides of the equation by 12, the least common multiple of 4,2,3.
3x=6x\left(\frac{1}{3}x-2\right)
Multiply 6 and 1 to get 6.
3x=6x\times \frac{1}{3}x-12x
Use the distributive property to multiply 6x by \frac{1}{3}x-2.
3x=6x^{2}\times \frac{1}{3}-12x
Multiply x and x to get x^{2}.
3x=\frac{6}{3}x^{2}-12x
Multiply 6 and \frac{1}{3} to get \frac{6}{3}.
3x=2x^{2}-12x
Divide 6 by 3 to get 2.
3x-2x^{2}=-12x
Subtract 2x^{2} from both sides.
3x-2x^{2}+12x=0
Add 12x to both sides.
15x-2x^{2}=0
Combine 3x and 12x to get 15x.
-2x^{2}+15x=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{-2x^{2}+15x}{-2}=\frac{0}{-2}
Divide both sides by -2.
x^{2}+\frac{15}{-2}x=\frac{0}{-2}
Dividing by -2 undoes the multiplication by -2.
x^{2}-\frac{15}{2}x=\frac{0}{-2}
Divide 15 by -2.
x^{2}-\frac{15}{2}x=0
Divide 0 by -2.
x^{2}-\frac{15}{2}x+\left(-\frac{15}{4}\right)^{2}=\left(-\frac{15}{4}\right)^{2}
Divide -\frac{15}{2}, the coefficient of the x term, by 2 to get -\frac{15}{4}. Then add the square of -\frac{15}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{15}{2}x+\frac{225}{16}=\frac{225}{16}
Square -\frac{15}{4} by squaring both the numerator and the denominator of the fraction.
\left(x-\frac{15}{4}\right)^{2}=\frac{225}{16}
Factor x^{2}-\frac{15}{2}x+\frac{225}{16}. 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-\frac{15}{4}\right)^{2}}=\sqrt{\frac{225}{16}}
Take the square root of both sides of the equation.
x-\frac{15}{4}=\frac{15}{4} x-\frac{15}{4}=-\frac{15}{4}
Simplify.
x=\frac{15}{2} x=0
Add \frac{15}{4} to both sides of the equation.