By hypothesis, a ski club charges $48 membership fee plus $18 per day to rent ski equipment. X represents the number of day.
So if someone wants to rent ski equipment for x days, the charges will be 18x dollars. In addition to that, he needs to pay 48 dollars as membership fee. So in total, he needs to pay 48 + 18x.
So the equation y = 48 + 18x represents the total cost of membership at the club when renting equipment for x days.
Hope this helps! :)
