For this case we have:
[tex]2b[/tex]: Variable that represents the amount of books Tim had.
k: Variable that represents the price of each book
y: Variable that represents the quantity of books not sold.
Then we have, according to the statement that, the quantity of books sold is given by:
[tex]2b-y[/tex]
Thus, the total dollar amount received for the books sold are:
[tex]k (2b-y)[/tex]
Answer:
Option A
