a group of 19 students want to see the show at the planetarium. Ticket cost $11 for each student who is a member of the planetarium's frequent visitor program and $13 for each student who is not a member. The total cost of the student tickets is $209. Let x represent the number of student in the group who are members of the frequent visitor program. Write an expression in term of x for the number of student in the group who are not member