\(\Leftrightarrow\left\{{}\begin{matrix}8-x\ge0\\x-2\ge0\\8-x\le\left(x-2\right)^2\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}2\le x\le8\\x^2-3x-4\ge0\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}2\le x\le8\\\left[{}\begin{matrix}x\ge4\\x\le-1\end{matrix}\right.\end{matrix}\right.\) \(\Rightarrow4\le x\le8\)