\(\left[{}\begin{matrix}x-0,\left(1\right)=1,9\\x-0,\left(1\right)=-1,9\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=1,9\\x=-1,9\end{matrix}\right.\)
\(\left[{}\begin{matrix}1,\left(23\right)-x=0,\left(72\right)\\1,\left(23\right)-x=-0,\left(72\right)\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=23\\x=23\end{matrix}\right.\)