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-\frac{1}{2}x\times 2x+2x\times 2=-2\times 6
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 2x, the least common multiple of 2,x.
-xx+2x\times 2=-2\times 6
Cancel out 2 and 2.
-x^{2}+2x\times 2=-2\times 6
Multiply x and x to get x^{2}.
-x^{2}+4x=-2\times 6
Multiply 2 and 2 to get 4.
-x^{2}+4x=-12
Multiply -2 and 6 to get -12.
-x^{2}+4x+12=0
Add 12 to both sides.
x=\frac{-4±\sqrt{4^{2}-4\left(-1\right)\times 12}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 4 for b, and 12 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-4±\sqrt{16-4\left(-1\right)\times 12}}{2\left(-1\right)}
Square 4.
x=\frac{-4±\sqrt{16+4\times 12}}{2\left(-1\right)}
Multiply -4 times -1.
x=\frac{-4±\sqrt{16+48}}{2\left(-1\right)}
Multiply 4 times 12.
x=\frac{-4±\sqrt{64}}{2\left(-1\right)}
Add 16 to 48.
x=\frac{-4±8}{2\left(-1\right)}
Take the square root of 64.
x=\frac{-4±8}{-2}
Multiply 2 times -1.
x=\frac{4}{-2}
Now solve the equation x=\frac{-4±8}{-2} when ± is plus. Add -4 to 8.
x=-2
Divide 4 by -2.
x=-\frac{12}{-2}
Now solve the equation x=\frac{-4±8}{-2} when ± is minus. Subtract 8 from -4.
x=6
Divide -12 by -2.
x=-2 x=6
The equation is now solved.
-\frac{1}{2}x\times 2x+2x\times 2=-2\times 6
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 2x, the least common multiple of 2,x.
-xx+2x\times 2=-2\times 6
Cancel out 2 and 2.
-x^{2}+2x\times 2=-2\times 6
Multiply x and x to get x^{2}.
-x^{2}+4x=-2\times 6
Multiply 2 and 2 to get 4.
-x^{2}+4x=-12
Multiply -2 and 6 to get -12.
\frac{-x^{2}+4x}{-1}=-\frac{12}{-1}
Divide both sides by -1.
x^{2}+\frac{4}{-1}x=-\frac{12}{-1}
Dividing by -1 undoes the multiplication by -1.
x^{2}-4x=-\frac{12}{-1}
Divide 4 by -1.
x^{2}-4x=12
Divide -12 by -1.
x^{2}-4x+\left(-2\right)^{2}=12+\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=12+4
Square -2.
x^{2}-4x+4=16
Add 12 to 4.
\left(x-2\right)^{2}=16
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{16}
Take the square root of both sides of the equation.
x-2=4 x-2=-4
Simplify.
x=6 x=-2
Add 2 to both sides of the equation.