Solve the equation -15 + 10y = 25 for y

Which equation represents the function on the graph?

Helena lost her marbles. but then she found them and put them in 44 bags with mm marbles in each bag. she had 33 marbles left over that didn't fit in the bags.

In order for the function to be linear, what must m be and why? m = 22 because the rate of change is 1. m = 20 because the rate of change is 3. m = 22 because the rate of change is -1. m = 20 because the rate of change is -3.