What is a Linear Function?
A linear function is an algebraic equation in which each term is either a constant or the product of a constant and (the first power of) a single variable. For example, a common equation,
Graphs of Linear Functions
The origin of the name "linear" comes from the fact that the set of solutions of such an equation forms a straight line in the plane. In the linear function graphs below, the constant,
![](../../../../../../../figures.boundless-cdn.com/34783/large/ss1dshpyt0acdewquvnj.jpg)
Graphs of linear functions
The blue line,
Vertical and Horizontal Lines
Vertical lines have an undefined slope, and cannot be represented in the form
Horizontal lines have a slope of zero and is represented by the form,