There are 24 pictures on a roll of film. adelle had 84 pictures from her trip home. she said that 12 other pictures were spoiled. how many rolls of film did adelle use

Three students, javier, sam, and corrine, participated in a fundraiser where people donated a certain amount of money per lap that the student ran. each student also had some initial donations that were collected before the run. the equations that represent each student's total donation, y, based on the number of laps ran, x, is shown below. match each equation with the correct rate of change for that student.