Geometry: Distance Between Points

Lesson Procedure:

Print the classroom lesson plan and worksheet questions (see below).

Lesson Excerpt:

Introduction
We have been working to figure out the measurement of different line segments. Today, we are going to continue with this work. Let’s begin.

On a Number Line
The first measurement that we are going to work to calculate is the distance between two points that are on a number line. When we calculate the distance on a number line, we are looking for the number of units between two points on that number line. Let’s start by looking at a number line.

To find the distance between two points on a number line, we take the absolute value of one point subtracted from the other point. In this example, we used A and B, but any two points can be substituted into this formula. Because we take the absolute value of the difference between the two points, it also doesn’t matter which order you choose to write them in. We could have just as easily written B minus A.

Continued...