С поянением пожалуйста 8 номер

Решите задачу:

$\left\{\begin{array}{c}5x+12\leq3x+7,\\x\ \textless \ 2x+3,\\2x+7\geq0;\end{array}\right. \left\{\begin{array}{c}5x-3x\leq7-12,\\x-2x\ \textless \ 3,\\2x\geq-7;\end{array}\right. \left\{\begin{array}{c}2x\leq-5,\\-x\ \textless \ 3,\\x\geq-3,5;\end{array}\right. \\ \left\{\begin{array}{c}x\leq-2,5,\\x\ \textgreater \ -3,\\x\geq-3,5;\end{array}\right. \left \{ {{x\leq-2,5, \atop {x\ \textgreater \ -3;} \right. \\ x\in(-3;-2,5]$