\[\left\{ \begin{matrix} x = - 2y - 5\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \\ - 4x^{2} - 8xy + 5y^{2} = 0 \\ \end{matrix} \right.\ \]
\[5y^{2} - 40y - 100 = 0\]
\[D = ( - 40)^{2} - 4 \cdot 5 \cdot ( - 100) =\]
\[= 1600 + 2000 = 3600;\ \ \ \]
\[\sqrt{D} = 60.\]
\[y_{1} = \frac{40 + 60}{2 \cdot 5} = \frac{100}{10} = 10;\ \ \ \]
\[\text{\ \ \ }y_{2} = \frac{40 - 60}{2 \cdot 5} = \frac{- 20}{10} = - 2\]
\[x_{1} = - 2 \cdot 10 - 5 = - 20 - 5 =\]
\[= - 25;\]
\[x_{2} = - 2 \cdot ( - 2) - 5 = 4 - 5 =\]
\[= - 1.\]
\[Ответ:( - 25;10);\ \ ( - 1;\ - 2).\]