Note that the right hand side is just a constant.
Take log on both sides:
\(\log_9 (9^y) = \log_9 \left(\dfrac{3^5 \cdot 9 \cdot 6}{27 \cdot 3}\right)\\ y = \log_9 \left(\dfrac{3^5 \cdot 9 \cdot 6}{27 \cdot 3}\right)\)
I will leave the simplification to you.