When it comes to line equations, one very common and important property is the slope of the line. The slope of the line, generally represented by the letter m, is the gradient or incline of the line and it is an important concept to understand in algebra and geometry. The higher the slope of a line, the steeper the line grade is. This variable is often used for further more complicated line equations and calculations so it’s an important piece of information to calculate correctly the first time around.

The concept of a line was originally introduced by Euclid of Alexandria, the Greek mathematician, who defined lines to be “breadthless length”. Lines can be composed of multiple line segments. A line segment is a portion of a line with two fixed endings, that contains every point in between the two.

To determine the slope of a straight line, you can use the slope of a line equation seen in the formula box below.

This equation is based around using any two given points on the line. The points are represented in standard x,y graphing format. Alternatively, if you don’t want to calculate this number yourself, you can use the free slope of a straight line calculator at the bottom of this page to help you solve your equation.