The drama club is selling tickets to their play to raise money for the show's expenses. Each student ticket sells for $4.50 and each adult ticket sells for $8. The auditorium can hold no more than 84 people. The drama club must make at least $560 from ticket sales to cover the show's costs. If 29 student tickets were sold, determine all possible values for the number of adult tickets that the drama club must sell in order to meet the show's expenses.