I am sorry, but nobody can help until you put the question. Assuming it is Algebra, I can write this as function which would be y = 3x + 14.99 . Also, x has to be greather than zero because you cannot undownload a movie. y can also be something like f (m). m means the movies you downloaded. So it could also be f = 3m + 14.99 . If you want to graph it, I could do it for you.