Даже не знаю как делать помогите

3) [latex]-2*7 \ \textless \ \frac{(8+x)*7}{7}\ \textless \ 4*7 \\ -14\ \textless \ 56+7x\ \textless \ 28 \\ -14-56\ \textless \ 56+7x-56\ \textless \ 28-56 \\ -70\ \textless \ 7x\ \textless \ -28 \\ \frac{-70}{7}\ \textless \ \frac{7x}{7}\ \textless \ \frac{-28}{7} \\ -10\ \textless \ x\ \textless \ -4[/latex] 4) [latex]-7*2 \leq \frac{(2x+1)*2}{2} \ \textless \ 2*2 \\ -14 \leq 2x+1\ \textless \ 4 \\ -14-1 \leq 2x+1-1\ \textless \ 4-1 \\ -15 \leq 2x\ \textless \ 3 \\ \frac{-15}{2} \leq \frac{2x}{2} \ \textless \ \frac{3}{2} \\ -7 \frac{1}{2} \leq x\ \textless \ 1\frac{1}{2} [/latex]