Ответ:

[tex][-0,2; +\infty)[/tex]

Объяснение:

[tex]\displaystyle \left \{ {{5a-1 \geq 0} \atop {a+8 \geq 0}} \right. \Leftrightarrow \left \{ {{5a \geq 1} \atop {a \geq -8}} \right. \Leftrightarrow \left \{ {{a \geq 0,2} \atop {a \geq -8}} \right. \Leftrightarrow a \geq 0,2 \Rightarrow a \in [-0,2; +\infty);[/tex]