Solve the inequality $LaTeX: \displaystyle \frac{9}{x^{2} - 9}<\frac{2}{x^{2} - x - 12}$

Getting zero on one side and factoring gives $LaTeX: \displaystyle \frac{9}{\left(x - 3\right) \left(x + 3\right)} - \frac{2}{\left(x - 4\right) \left(x + 3\right)}< 0$ . This gives the least common denominator as $LaTeX: \displaystyle \left(x - 4\right) \left(x - 3\right) \left(x + 3\right)$ . Building each fraction to get the common denominator gives $LaTeX: \displaystyle \frac{9 x - 36 - (2 x - 6)}{\left(x - 4\right) \left(x - 3\right) \left(x + 3\right)} < 0$ . Simplifying gives $LaTeX: \displaystyle \frac{7 x - 30}{\left(x - 4\right) \left(x - 3\right) \left(x + 3\right)}<0$ . The inequality can change signs at the zeros of the numerator, $LaTeX: \displaystyle \left\{\frac{30}{7}\right\}$ , or the zeros of the denominator $LaTeX: \displaystyle \left\{-3, 3, 4\right\}$ . Making a sign chart gives: This gives the solution $LaTeX: \displaystyle \left(-3, 3\right) \cup \left(4, \frac{30}{7}\right)$