Answer:
y will represent the cost of one audio book.
Step-by-step explanation:
Here, the cost of 3 music albums and 5 audio books is $49.60 and 1 music album and 2 audio books is $20.50,
Since, there are two unknown values,
First one is the cost of one music album,
Second one is the cost of one audio book,
We know that, for finding an unknown value we take a variable,
If we have variables x and y in which x represent the cost of one music album, then y must represent the cost of one audio album.