Answer
$\{2\}$
Work Step by Step
Step 1. Rewrite the equation to isolate the radical. We have $\sqrt {8-2x}=x$
Step 2. Take the square on both sides to get $8-2x=x^2$, $x^2+2x-8=0$ and $(x+4)(x-2)=0$
Step 3. Test the solutions $x=-4, 2$ in the original equation. We should discard $x=-4$ and keep $x=2$ as the answer.
