\[\frac{x - 7}{x(x + 7)}\]
\[Не\ имеет\ смысла\ при\ \]
\[x(x + 7) = 0\]
\[x = 0\ \ \ \ \ \ \ \ x + 7 = 0\]
\[\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ x = - 7\]
\[Ответ:x = 0;\ \ x = - 7.\]