Решите систему неравенств: x^2+x-20<=0; 2x+10<=0.

\[\left\{ \begin{matrix} x² + x - 20 \leq 0\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \\ 2x + 10 \leq 0,\ \ x \leq - 5 \\ \end{matrix} \right.\ \]

\[x^{2} + x - 20 = 0\]

\[x_{1} + x_{2} = - 1,\ \ x_{1} = - 20\]

\[x_{1} \cdot x_{2} = - 5,\ \ x_{2} = 4\]

\[Ответ:\ \left\{ - 5 \right\}.\]