\(\left|4-x\right|=1-4x\)
\(\Rightarrow\left[{}\begin{matrix}4-x=1-4x\left(ĐK:x\ge4\right)\\-4+x=1-4x\left(ĐK:x< 4\right)\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}4=1-3x\Rightarrow3x=-3\Rightarrow x=-1\left(KTM\right)\\-4=1-5x\Rightarrow5x=5\Rightarrow x=1\left(TM\right)\end{matrix}\right.\)
Vậy \(x=1\)