\(\Leftrightarrow x^2-\left(y+1\right)x+y^2-y=0\)
\(\Delta=\left(y+1\right)^2-4\left(y^2-y\right)\ge0\)
\(\Leftrightarrow-3y^2+6y+1\ge0\)
\(\Rightarrow y=\left\{0;1;2\right\}\)
- Với \(y=0\Rightarrow x^2-x=0\Rightarrow\left[{}\begin{matrix}x=0\\x=1\end{matrix}\right.\)
- Với \(y=1\Rightarrow x^2-2x=0\Rightarrow\left[{}\begin{matrix}x=0\\x=2\end{matrix}\right.\)
- Với \(y=2\Rightarrow x^2-3x+2=0\Rightarrow\left[{}\begin{matrix}x=1\\x=2\end{matrix}\right.\)