Answer
`|1/3x - 2| = |1/6x + 1|`
`=>` $\left[\begin{matrix} \dfrac{1}{3}x - 2 = \dfrac{1}{6}x + 1\\ \dfrac{1}{3}x - 2 = -(\dfrac{1}{6}x + 1)\end{matrix}\right.$
`=>` $\left[\begin{matrix} \dfrac{1}{3}x - \dfrac{1}{6}x = 1 + 2\\ \dfrac{1}{3}x - 2 = -\dfrac{1}{6}x - 1\end{matrix}\right.$
`=>` $\left[\begin{matrix} \dfrac{1}{6}x = 3\\ \dfrac{1}{3}x + \dfrac{1}{6}x = -1 + 2\end{matrix}\right.$
`=>` $\left[\begin{matrix} x = 3 : \dfrac{1}{6}\\ \dfrac{1}{2}x = 1\end{matrix}\right.$
`=>` $\left[\begin{matrix} x = 18\\ x = 1 : \dfrac{1}{2}\end{matrix}\right.$
`=>` $\left[\begin{matrix} x = 18\\ x = 2\end{matrix}\right.$
$\text{Vậy}$ `x \in {18 ; 2}`
