\frac{(\sqrt{7} - 2)(\sqrt{7} - 3)}{(\sqrt{7} + 3)(\sqrt{7} - 3)} = \frac{(7 - 3\sqrt{7} - 2\sqrt{7} + 6)}{7 - 9} = \frac{13 - 5\sqrt{7}}{-2} = -\frac{13}{2} + \frac{5\sqrt{7}}{2}