Question

срочно помогите с первым вариантом даю 20баллов

Answer 1

1)
a)
$4+12x\ \textgreater \ 7+13x \\-x\ \textgreater \ 3 \\x\ \textless \ -3 \\ x\in(-\infty;-3)$

b)
$-(2-3x)+4(6+x)\ \textgreater \ 1 \\ -2+3x+24+4x\ \textgreater \ 1 \\7x\ \textgreater \ -21 \\ x\ \textgreater \ -3 \\x\in(-3;+\infty)$

2)
$\left \{ {{3x+4 \leq 4x+6} \atop {x-5 \leq 4-2x}} \right. \\\\ \left \{ {{-x \leq2} \atop {3x\leq9}} \right. \\\\ \left \{ {{x \geq -2} \atop {x\leq3}} \right. \\\\ x\in[-2;3]$

3)
$-3\ \textless \ 2-5x\ \textless \ 1 \\ -3-2\ \textless \ -5x\ \textless \ 1-2 \\-5\ \textless \ -5x\ \textless \ -1 \\1\ \textless \ 5x\ \textless \ 5 \\ 0.2\ \textless \ x\ \textless \ 1 \\ x\in(0.2;1)$