Ответ: x∈[-7;7,5].

Объяснение:

[tex]\displaystyle\\\left \{ {{(x+8)(x-1)-x(x+5)\leq 7} \atop {\frac{x+1}{6}-x\leq 6\ |*6 }} \right. \ \ \ \ \left \{ {{x^2+7x-8-x^2-5x\leq 7} \atop {x+1-6x\leq 36}} \right. \\\\\\\left \{ {{2x\leq 15\ |:2} \atop {-5x\leq 35\ |:(-5)}} \right. \ \ \ \ \left \{ {{x\leq 7,5} \atop {x\geq -7}} \right. \ \ \ \ \Rightarrow\ \ \ \ \ \ x\in[-7;7,5].[/tex]