Evaluate the limit LaTeX:  \displaystyle \lim_{x \to -7}\frac{5 x^{2} + 80 x + 315}{7 x^{2} + 43 x - 42}

The limit is an indeterminate form of the type LaTeX:  \displaystyle \frac{0}{0} . Using L'Hospitial's rule and then the evaluation theorem gives: LaTeX:   \lim_{x \to -7}\frac{5 x^{2} + 80 x + 315}{7 x^{2} + 43 x - 42} = \lim_{x \to -7}\frac{10 x + 80}{14 x + 43} = \frac{10 (-7) + 80}{14 (-7) + 43} = - \frac{2}{11}