\(y^2-y+x^2=2xy-x\)
\(\Leftrightarrow x^2-2xy+y^2+x-y=0\)
\(\Leftrightarrow\left(x-y\right)^2+x-y=0\)
\(\Leftrightarrow\left(x-y\right)\left(x-y+1\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}y=x\\y=x+1\end{matrix}\right.\)
Thay xuống dưới:
\(\left[{}\begin{matrix}2x^2+x^2-x^2+x-3=0\\2x^2+x-\left(x+1\right)^2+x+1-3=0\end{matrix}\right.\) \(\Leftrightarrow...\)