\(\Leftrightarrow\) 5.|x-1| -3x-6 = -3x + 12
\(\Leftrightarrow5\left|x-1\right|=18\)
Ta có |x -1| = \(\left\{\begin{matrix}x-1\\1-x\end{matrix}\right.\)
Th1: 5. (x -1) =18
\(\Leftrightarrow5x-5=18\)
\(\Leftrightarrow x=\frac{23}{5}\)
Th2: 5.(1-x) = 18
\(\Leftrightarrow-5x=13\)
\(\Leftrightarrow x=-\frac{13}{5}\)
Vậy pt có nghiệm là S=\(\left\{-\frac{13}{5};\frac{23}{5}\right\}\)