A business has $11,080 to spend on new laptops and tablet computers for its salespeople. The laptops cost $515 each. The tablets cost $285 each. The business wants each salesperson to have either a laptop or a tablet. There are 30 salespeople. Create a system of equations that models how many of each type of computer the business should buy.
a. 515x + 285y = 11,080
x + y = 30
b. 515x + 285y = 30
x + y = 11,080
c. 515x + y = 30
x + 285y = 11,080
d. x + 285y = 30
515x + y = 11,080