ĐKXĐ:\(\left\{{}\begin{matrix}x-2\ne0\\x-5\ne0\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}x\ne2\\x\ne5\end{matrix}\right.\)
\(\frac{3x}{x-2}-\frac{x}{x-5}=\frac{3x}{\left(x-2\right)\left(5-x\right)}\)
\(\frac{3x\left(5-x\right)}{\left(x-2\right)\left(5-x\right)}+\frac{x\left(x-2\right)}{\left(x-2\right)\left(5-x\right)}-\frac{3x}{\left(x-2\right)\left(5-x\right)}=0\)
\(15x-3x^2+x^2-2x-3x=0\)
\(10x-2x^2=0\)
\(2x.\left(5-x\right)=0\)
\(\Rightarrow\left\{{}\begin{matrix}2x=0\\5-x=0\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}x=0\left(chọn\right)\\x=5\left(loại\right)\end{matrix}\right.\)