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x\left(x-2\right)=2\left(x+2\right)
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 4x, the least common multiple of 4,2x.
x^{2}-2x=2\left(x+2\right)
Use the distributive property to multiply x by x-2.
x^{2}-2x=2x+4
Use the distributive property to multiply 2 by x+2.
x^{2}-2x-2x=4
Subtract 2x from both sides.
x^{2}-4x=4
Combine -2x and -2x to get -4x.
x^{2}-4x-4=0
Subtract 4 from both sides.
x=\frac{-\left(-4\right)±\sqrt{\left(-4\right)^{2}-4\left(-4\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -4 for b, and -4 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-4\right)±\sqrt{16-4\left(-4\right)}}{2}
Square -4.
x=\frac{-\left(-4\right)±\sqrt{16+16}}{2}
Multiply -4 times -4.
x=\frac{-\left(-4\right)±\sqrt{32}}{2}
Add 16 to 16.
x=\frac{-\left(-4\right)±4\sqrt{2}}{2}
Take the square root of 32.
x=\frac{4±4\sqrt{2}}{2}
The opposite of -4 is 4.
x=\frac{4\sqrt{2}+4}{2}
Now solve the equation x=\frac{4±4\sqrt{2}}{2} when ± is plus. Add 4 to 4\sqrt{2}.
x=2\sqrt{2}+2
Divide 4+4\sqrt{2} by 2.
x=\frac{4-4\sqrt{2}}{2}
Now solve the equation x=\frac{4±4\sqrt{2}}{2} when ± is minus. Subtract 4\sqrt{2} from 4.
x=2-2\sqrt{2}
Divide 4-4\sqrt{2} by 2.
x=2\sqrt{2}+2 x=2-2\sqrt{2}
The equation is now solved.
x\left(x-2\right)=2\left(x+2\right)
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 4x, the least common multiple of 4,2x.
x^{2}-2x=2\left(x+2\right)
Use the distributive property to multiply x by x-2.
x^{2}-2x=2x+4
Use the distributive property to multiply 2 by x+2.
x^{2}-2x-2x=4
Subtract 2x from both sides.
x^{2}-4x=4
Combine -2x and -2x to get -4x.
x^{2}-4x+\left(-2\right)^{2}=4+\left(-2\right)^{2}
Divide -4, the coefficient of the x term, by 2 to get -2. Then add the square of -2 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-4x+4=4+4
Square -2.
x^{2}-4x+4=8
Add 4 to 4.
\left(x-2\right)^{2}=8
Factor x^{2}-4x+4. 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-2\right)^{2}}=\sqrt{8}
Take the square root of both sides of the equation.
x-2=2\sqrt{2} x-2=-2\sqrt{2}
Simplify.
x=2\sqrt{2}+2 x=2-2\sqrt{2}
Add 2 to both sides of the equation.