For this case we have the following data:
A shipping fee of $ 1.99 is charged for each book sold.
There is a fixed fee of 3 dollars per order.
We must express the total cost by a function of the form
.
If x represents the number of books sold, we have an expression of the form:

That is, according to the number of books sold, represented by x, a different value will be obtained for the total cost given by f (x). For example:
If 3 books are sold, we have:

Thus, the total cost of 3 books is 8.97 dollars.
Answer:
