Math 1324: About Chapter 5, Simple vs. Compound Interest

Math 1324 students often get hung up on the formula I=Prt and want to use it EVERY time they are asked to calculate the interest (or "interest earned.")
Here I make an argument for why you should think. "I = A - P," instead, as that works for BOTH compound and simple interest. I also give an example of comparing their two graphs at once, using the graphing calculator.