Đáp án + Giải thích các bước giải:
`|3x-2|-x=7`
`->|3x-2|=x+7` `(x>= -7)`
`->` \(\left[ \begin{array}{l}3x-2=x+7\\3x-2=-x-7\end{array} \right.\)
`->` \(\left[ \begin{array}{l}3x-x=2+7\\3x+x=2-7\end{array} \right.\)
`->` \(\left[ \begin{array}{l}2x=9\\4x=-5\end{array} \right.\)
`->` \(\left[ \begin{array}{l}x=\dfrac{9}{2}\ (tm)\\x=-\dfrac{5}{4}\ (tm)\end{array} \right.\)
Vậy `x\in {9/2;-5/4}`
