Compare the two functions described below.

Function 1: Originally there were 40 people living at Schondel City. The city's population is growing and the amount of people living in the city triples daily!

Function 2: y = 15 • 0.8^x

Function 1 is modeled by the equation:

y = 40 + 3x

where x is the number of days and y is the city's population or amount of people living in the city.

This is a linear equation because all of the terms have exponent 1.

Function 2 is a non-linear equation. Specifically, it is an example of an exponential equation because its variable x is found in the exponent.