Упростите выражение (a-18)/(2a-12)-(a-6)/(2a+12)+50/(a^2-36).

\[\frac{a - 18}{2a - 12} - \frac{a - 6}{2a + 12} + \frac{50}{a^{2} - 36} =\]

\[= \frac{a - 18^{\backslash a + 6}}{2(a - 6)} - \frac{a - 6^{\backslash a - 6}}{2(a + 6)} + \frac{50^{\backslash 2}}{(a - 6)(a + 6)} =\]

\[= \frac{a^{2} - 18a + 6a - 108 - a^{2} + 12a - 36 + 100}{2(a - 6)(a + 6)} =\]

\[= \frac{- 44}{2(a - 6)(a + 6)} = - \frac{22}{a^{2} - 36} =\]

\[= \frac{22}{36 - a²}\]