\[\boxed{\mathbf{1327}\mathbf{.}}\]
\[1)\ x^{2} - 2x - 15 = 0\]
\[D = 4 + 60 = 64\]
\[x_{1} = \frac{2 - 8}{2} = - \frac{6}{2} = - 3;\]
\[x_{2} = \frac{2 + 8}{2} = \frac{10}{2} = 5.\]
\[Ответ:\ - 3;\ 5.\]
\[2)\ 3x^{2} + 4x - 4 = 0\]
\[D = 16 + 48 = 64\]
\[x_{1} = \frac{- 4 - 8}{2 \bullet 3} = - \frac{12}{6} = - 2;\]
\[x_{2} = \frac{- 4 + 8}{2 \bullet 3} = \frac{4}{6} = \frac{2}{3}.\]
\[Ответ:\ - 2;\ \frac{2}{3}.\]