The drama club is selling tickets to their play to raise money for the show's expenses. Each student ticket sells for $8 and each adult ticket sells for $10.50. The auditorium can hold a maximum of 105 people. The drama club must make at least $990 from ticket sales to cover the show's costs. If 65 adult tickets were sold, determine the minimum number of student tickets that the drama club must sell in order to meet the show's expenses. If there are no possible solutions, submit an empty answer.