\[x^{2} + 11x + q = 0;\ \ x_{1} = - 7\]
\[x_{1} + x_{2} = - 11\]
\[- 7 + x_{2} = - 11\]
\[x_{2} = - 4.\]
\[x_{1} \cdot x_{2} = q\]
\[( - 7) \cdot ( - 4) = q\]
\[q = 28.\]
\[Ответ:x_{2} = - 4;q = 28.\]