\(x\left(y+1\right)=-3\)
\(\rightarrow\left\{{}\begin{matrix}x=-3\\y+1=1\end{matrix}\right.\) hoặc \(\left\{{}\begin{matrix}x=3\\y+1=-1\end{matrix}\right.\) hoặc \(\left\{{}\begin{matrix}x=-1\\y+1=3\end{matrix}\right.\) hoặc \(\left\{{}\begin{matrix}x=1\\y+1=-3\end{matrix}\right.\)
Giải ta được các nghiệm
\(\left(x;y\right)=\left(-3;0\right);\left(3;-2\right);\left(-1;2\right);\left(1;-4\right)\)
`x.(y+1)= -3`
\(\Rightarrow\left[{}\begin{matrix}\left\{{}\begin{matrix}y+1=1\\x=-3\end{matrix}\right.\\\left\{{}\begin{matrix}y+1=-1\\x=3\end{matrix}\right.\\\left\{{}\begin{matrix}y+1=3\\x=-1\end{matrix}\right.\\\left\{{}\begin{matrix}y+1=-3\\x=1\end{matrix}\right.\end{matrix}\right.\)\(\Rightarrow\left[{}\begin{matrix}\left\{{}\begin{matrix}y=0\\x=-3\end{matrix}\right.\\\left\{{}\begin{matrix}y=-2\\x=-3\end{matrix}\right.\\\left\{{}\begin{matrix}y=2\\x=1\end{matrix}\right.\\\left\{{}\begin{matrix}y=-4\\x=1\end{matrix}\right.\end{matrix}\right.\)