Description: Learn to recognize if a function is linear. Created by Sal Khan and Monterey Institute for Technology and Education. So linear functions, the way to tell them is for any given change in x, is the change in y always going to be the same value. If it's always going to be the same value, you're dealing with a linear function. If they're not, then we're dealing with a non-linear function.*Teacher Advisor is 100% free.