The difference between x and 4 is greater than 10

When only separate discreet points are graphed it is called?

Aschool puts on a play. the play costs $1,200 in expenses. the students charge $4.00 for tickets. there will be one performance of the play in an auditorium that seats 500 people. what is the domain of the function that shows the profit as a function of the number of tickets sold?  

Which graph represents the function f(x)=4[x]?