Could you please help me answer this?
Fund Raising. A charity organization wishes to raise at least $12,000 from a movie premiere to be held at a theatre with 800 seats. The ticket prices are to be $20 and $15, with at least 500 tickets to be sold at $20.
a. If x tickets at $20 and y tickets at $15 are sold, what is the system of inequalities involving x and y?
b. Draw a sketch of the graph of the system in part (a) that shows the region of permissible values of x and y.