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xx+x\left(-2\right)=4x-8
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
x^{2}+x\left(-2\right)=4x-8
Multiply x and x to get x^{2}.
x^{2}+x\left(-2\right)-4x=-8
Subtract 4x from both sides.
x^{2}-6x=-8
Combine x\left(-2\right) and -4x to get -6x.
x^{2}-6x+8=0
Add 8 to both sides.
x=\frac{-\left(-6\right)±\sqrt{\left(-6\right)^{2}-4\times 8}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -6 for b, and 8 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-6\right)±\sqrt{36-4\times 8}}{2}
Square -6.
x=\frac{-\left(-6\right)±\sqrt{36-32}}{2}
Multiply -4 times 8.
x=\frac{-\left(-6\right)±\sqrt{4}}{2}
Add 36 to -32.
x=\frac{-\left(-6\right)±2}{2}
Take the square root of 4.
x=\frac{6±2}{2}
The opposite of -6 is 6.
x=\frac{8}{2}
Now solve the equation x=\frac{6±2}{2} when ± is plus. Add 6 to 2.
x=4
Divide 8 by 2.
x=\frac{4}{2}
Now solve the equation x=\frac{6±2}{2} when ± is minus. Subtract 2 from 6.
x=2
Divide 4 by 2.
x=4 x=2
The equation is now solved.
xx+x\left(-2\right)=4x-8
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
x^{2}+x\left(-2\right)=4x-8
Multiply x and x to get x^{2}.
x^{2}+x\left(-2\right)-4x=-8
Subtract 4x from both sides.
x^{2}-6x=-8
Combine x\left(-2\right) and -4x to get -6x.
x^{2}-6x+\left(-3\right)^{2}=-8+\left(-3\right)^{2}
Divide -6, the coefficient of the x term, by 2 to get -3. Then add the square of -3 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-6x+9=-8+9
Square -3.
x^{2}-6x+9=1
Add -8 to 9.
\left(x-3\right)^{2}=1
Factor x^{2}-6x+9. 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-3\right)^{2}}=\sqrt{1}
Take the square root of both sides of the equation.
x-3=1 x-3=-1
Simplify.
x=4 x=2
Add 3 to both sides of the equation.