Решите пример, пожалуйста!!! Решение сфотографируете❤️

Решите задачу:

$( \frac{12- a^{2}}{a+3} + a-3 ): (\frac{1}{a+3} + \frac{a}{a^{2}-9} + \frac{5}{3 - a})= \\ = ( \frac{12- a^{2}}{a+3} + \frac{(a-3)(a+3)}{a+3} ):( \frac{a-3}{(a-3)(a+3)} + \frac{a}{a^{2}-9} - \frac{5}{a-3})= \\ = \frac{12- a^{2} + a^{2}-9}{a+3}:( \frac{a-3}{a^{2}-9} + \frac{a}{a^{2}-9} - \frac{5(a+3)}{(a-3)(a+3)})= \\ = \frac{3}{a+3}: \frac{a-3+ a - 5a - 15}{a^{2}-9} = \frac{3}{a+3}:\frac{- 3a - 18}{a^{2}-9}= \\ =\frac{3}{a+3}* \frac{a^{2}-9}{- 3a - 18}=\frac{3}{a+3}* \frac{a^{2}-9}{- 3(a +6)}= \\$
$=\frac{3(a-3)(a+3)}{-(a+3)* 3(a +6)}= \frac{a-3}{-(a +6)}=\frac{3-a}{a +6} \\$