Question

Elleanna is planning to join a DVD club and is investigating the options for membership. Option 1 is $20 membership fee $1.25 rental change for each DVD rented. Option 2 has no rental fee and changes $2.50 for each DVD rented. How many DVDs would Elleanna have to rent in order for the total cost of Option 1 to be equal to option 2?

Answer 1

Option 1 : 20 + 1.25d
option 2 : 2.50d

when will they be equal......so set them equal to each other
20 + 1.25d = 2.50d
20 = 2.50d - 1.25d
20 = 1.25d
20 / 1.25 = d
16 = d.....so they will be equal at 16 dvd rentals