Question

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

Answer 1

X = number of students who are members.
19-x is the number of people who are not members. x number of people paid $11 for tickets and (19-x) number of people paid $13.$11x+$13(19-x)=$209 for the total cost of the tickets.
$11x+ $247-$13x=$209 $11x-13x = $209 - $247

$-2x = $-38

divide -2 by both sides

x=19, meaning that all of the students are members.