Giải thích các bước giải:
Để $-2x-11\quad\vdots\quad 3x+2$
$\to 2x+11\quad\vdots\quad 3x+2$
$\to 3(2x+11)\quad\vdots\quad 3x+2$
$\to 6x+33\quad\vdots\quad 3x+2$
$\to 6x+4+29\quad\vdots\quad 3x+2$
$\to 2(3x+2)+29\quad\vdots\quad 3x+2$
$\to 29\quad\vdots\quad 3x+2$
$\to 3x+2\in\{29,-1\}$ vì $3x+2$ chia 3 dư 2
$\to x\in\{9,-1\}$
$\to $Để $-2x-11\quad\vdots\quad 3x+2\to x\in\{9,-1\}$
