\(\Rightarrow\left|x-1\right|+2\left|x-1\right|=4\\ \Rightarrow3\left|x-1\right|=4\\ \Rightarrow\left|x-1\right|=\dfrac{4}{3}\\ \Rightarrow\left[{}\begin{matrix}x-1=\dfrac{4}{3}\\1-x=\dfrac{4}{3}\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=\dfrac{7}{3}\\x=-\dfrac{1}{3}\end{matrix}\right.\)