\(\left(x-2\right)^2-2x\left(x-3\right)=4\\ \)
\(x^2-2.2.x+2^2-2x^2+6x=4\)
\(x^2-4x+4-2x^2+6x=4\)
\(-x^2+2x+4=4\)
\(x\left(-x+2\right)=4-4\)
\(x\left(-x+2\right)=0\)
\(\Rightarrow\left\{{}\begin{matrix}x=0\\-x-2=0\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}x=0\\x=-2\end{matrix}\right.\)
Vậy --