Coach Smith purchased x footballs and y basketballs at a sporting goods store. The price of one football was $35.00 and the price of one basketball was $45.00. There was no tax included on the purchase. Part A. Write an expression that can be used to find the total cost of x footballs and y basketballs. Part B. The total cost of the purchase was $455.00. If Coach Smith purchased 4 footballs, find the number of basketballs he purchased.