Solve for x
x=\sqrt{2}\approx 1.414213562
x=-\sqrt{2}\approx -1.414213562
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8x-2x^{2}=8x-4
Use the distributive property to multiply 2x by 4-x.
8x-2x^{2}-8x=-4
Subtract 8x from both sides.
-2x^{2}=-4
Combine 8x and -8x to get 0.
x^{2}=\frac{-4}{-2}
Divide both sides by -2.
x^{2}=2
Divide -4 by -2 to get 2.
x=\sqrt{2} x=-\sqrt{2}
Take the square root of both sides of the equation.
8x-2x^{2}=8x-4
Use the distributive property to multiply 2x by 4-x.
8x-2x^{2}-8x=-4
Subtract 8x from both sides.
-2x^{2}=-4
Combine 8x and -8x to get 0.
-2x^{2}+4=0
Add 4 to both sides.
x=\frac{0±\sqrt{0^{2}-4\left(-2\right)\times 4}}{2\left(-2\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -2 for a, 0 for b, and 4 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-2\right)\times 4}}{2\left(-2\right)}
Square 0.
x=\frac{0±\sqrt{8\times 4}}{2\left(-2\right)}
Multiply -4 times -2.
x=\frac{0±\sqrt{32}}{2\left(-2\right)}
Multiply 8 times 4.
x=\frac{0±4\sqrt{2}}{2\left(-2\right)}
Take the square root of 32.
x=\frac{0±4\sqrt{2}}{-4}
Multiply 2 times -2.
x=-\sqrt{2}
Now solve the equation x=\frac{0±4\sqrt{2}}{-4} when ± is plus.
x=\sqrt{2}
Now solve the equation x=\frac{0±4\sqrt{2}}{-4} when ± is minus.
x=-\sqrt{2} x=\sqrt{2}
The equation is now solved.
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Limits
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