Reserved tickets for the basketball game cost $3 each and general admission tickets $2. Let x be the number of reserdes tickets a person sells and let y be the number of general admission tickets that person sells.
x tickets at $3 each would be 3 * x, or 3x
y tickets at $2 each would be 2 * y, or 2y
Since the total value of all x and y tickets must be $30, then 3x + 2y = 30