A bookstore is deciding what price it should charge for a certain book. After research, the store finds that if the book's price is p dollars (where p≤32), then the number of books sold per month is 128-4p. What price should the store charge to maximize its revenue?
revenue = price * #sold
= p * (128-4p)
= -4p2 + 128p max p will be - b/2a = -128/-8 = 16
max revenue will be -4(162) + 128 (16) = 1024