Ta có : xy - 2x = 0
=> x(y - 2) = 0
=> \(\orbr{\begin{cases}x=0\\y-2=0\end{cases}}\)
<=> \(\orbr{\begin{cases}x=0\\y=2\end{cases}}\)
\(\left(x-4\right)\left(x-3\right)=0\Rightarrow\hept{\begin{cases}x-3=0\\x-4=0\end{cases}}\)
\(\Rightarrow\hept{\begin{cases}x-3=0\Rightarrow x=3\\x-4=0\Rightarrow x=4\end{cases}}\)
Vậy..