Beau sold hardcover books for $⁢15 each and paperback books for $⁢10 each. He earned a total of $⁢350 from selling these books. Let x be the number of hardcover books Beau sold and y be the number of paperback books. The system of equations that models this scenario is: 15 x plus 10 y is equal to 350 x plus y is equal to 30 How many hardcover and paperback books did Beau sell?