Final answer:
The equivalent expression to log₉(xy) is log₉(x) + log₉(y).
Step-by-step explanation:
The logarithm of a product of two numbers is the sum of the logarithms of the two numbers. So, log₉(xy) can be written as log₉(x) + log₉(y). Therefore, the equivalent expression to log₉(xy) is log₉(x) + log₉(y).