\[y = - 3x^{2} - 6x + 5 \Longrightarrow ветви\ \]
\[вниз.\]
\[x_{0} = \frac{6}{- 6} = - 1;\ \ \]
\[y_{0} = - 3 + 6 + 5 = 8\]
\[( - 1;8).\]