Question

помогите развязать
|3x+1|≤ x+7

Answer 1

$|3x+1| leq x+7$

$left { {{3x+1 leq x+7} atop {3x+1 geq -x-7}} right.$

$left { {{3x-x leq 7-1} atop {3x+x geq -1-7}} right.$

$left { {{2xleq 6} atop {4x geq-8}} right.$

$left { {{xleq 3} atop {x geq-2}} right.$

Ответ: [-2;3]