Đáp án:
$\rm \begin{cases}x+y=m-1\\x-y=m+3\end{cases}\\\Leftrightarrow \begin{cases}2x=2m+2\\x-y=m+3\end{cases}\\\Leftrightarrow \begin{cases}x=m+1\\y=x-m-3=-2\end{cases}\\x_{o}=y_{o}^2\\\Leftrightarrow m+1=4\\\Leftrightarrow m=3\\Vậy\,\,m=3\,\,thì\,\,x_{o}=y_{o}^2$