2.1.10 Calculation of limits

Problem: Find the limit: \[ \lim _{n \rightarrow \infty} \frac{(3 n+6)^{2}\left(3 n^{4}+6 n^{3}-6 n-5\right)}{\left(-2 n^{2}+8 n+3\right)(-3 n-7)^{4}} \]