\(\sqrt{-2x^2+6}=x-1\)
\(\Leftrightarrow\left\{{}\begin{matrix}x-1\ge0\\-2x^2+6=\left(x-1\right)^2\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}x\ge1\\3x^2-2x-5=0\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}x\ge1\\\left[{}\begin{matrix}x=-1\\x=\frac{5}{3}\end{matrix}\right.\end{matrix}\right.\) \(\Rightarrow x=\frac{5}{3}\)