Ivan saves 20% of his monthly paycheck for music equipment. he earned $335 last month. how much money did ivan save for music equipment?

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.