Solve for x
x=2
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\sqrt{8-4x}=x-2
Subtract 2 from both sides of the equation.
\left(\sqrt{8-4x}\right)^{2}=\left(x-2\right)^{2}
Square both sides of the equation.
8-4x=\left(x-2\right)^{2}
Calculate \sqrt{8-4x} to the power of 2 and get 8-4x.
8-4x=x^{2}-4x+4
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-2\right)^{2}.
8-4x-x^{2}=-4x+4
Subtract x^{2} from both sides.
8-4x-x^{2}+4x=4
Add 4x to both sides.
8-x^{2}=4
Combine -4x and 4x to get 0.
-x^{2}=4-8
Subtract 8 from both sides.
-x^{2}=-4
Subtract 8 from 4 to get -4.
x^{2}=\frac{-4}{-1}
Divide both sides by -1.
x^{2}=4
Fraction \frac{-4}{-1} can be simplified to 4 by removing the negative sign from both the numerator and the denominator.
x=2 x=-2
Take the square root of both sides of the equation.
2+\sqrt{8-4\times 2}=2
Substitute 2 for x in the equation 2+\sqrt{8-4x}=x.
2=2
Simplify. The value x=2 satisfies the equation.
2+\sqrt{8-4\left(-2\right)}=-2
Substitute -2 for x in the equation 2+\sqrt{8-4x}=x.
6=-2
Simplify. The value x=-2 does not satisfy the equation because the left and the right hand side have opposite signs.
x=2
Equation \sqrt{8-4x}=x-2 has a unique solution.
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