\[\left\{ \begin{matrix} 2x² + 11x - 6 \leq 0 \\ x² + 8x \leq 0\ \ \ \ \ \ \ \ \ \ \ \ \\ \end{matrix} \right.\ \]
\[2x^{2} + 11x - 6 = 0\]
\[D = 121 + 48 = 169\]
\[x_{1} = \frac{- 11 + 13}{4} = 0,5\]
\[x_{2} = \frac{- 11 - 13}{4} = - 6\]
\[\lbrack - 6;0,5\rbrack.\]
\[x(x + 8) = 0\]
\[x = 0,\ \ x = - 8\]
\[\lbrack - 8;0\rbrack.\]
\[Ответ:\lbrack - 6;0\rbrack.\]