Question 1041590
The constant is the profit the band makes when x=0, and that occurs when the ticket price is $63.  As ticket prices increase, initially the profits increase, too, but eventually people stop buying the tickets at a rate that has the profits decrease.  
It can be shown (not part of the answer needed) that when x= about 8.5, or an increase in ticket price of 8.5*20, or $170, the maximum revenue is obtained.