Ta có: \(7\left(x-1\right)+2x\left(1-x\right)=0\)
\(\Leftrightarrow7\left(x-1\right)-2x\left(x-1\right)=0\)
\(\Leftrightarrow\left(7-2x\right)\left(x-1\right)=0\)
\(\Leftrightarrow\orbr{\begin{cases}7-2x=0\\x-1=0\end{cases}}\Rightarrow\orbr{\begin{cases}x=\frac{7}{2}\\x=1\end{cases}}\)