\(3x.\left(x-10\right)=\left(x-10\right)\)
\(\Rightarrow3x-\left(x-10\right)-\left(x-10\right)=0\)
\(\Rightarrow\left(3x-1\right)\left(x-10\right)=0\)
\(\Leftrightarrow\orbr{\begin{cases}3x-1=0\\x-10=0\end{cases}\Leftrightarrow\orbr{\begin{cases}x=\frac{1}{3}\\10\end{cases}}}\)