\[\frac{x^{2} + 7x}{x + 8} = \frac{8}{x + 8};\ \ \ \ x \neq - 8\]
\[x^{2} + 7x - 8 = 0\]
\[x_{1} + x_{2} = - 7;\ \ \ x_{1} \cdot x_{2} = - 8\]
\[x_{1} = - 8\ (не\ подходит);x_{2} = 1.\]
\[Ответ:x = 1.\]