Geometry: Distance Formula

Objectives:

• Students will review using the Pythagorean Theorem to find the distance of the two points of the hypotenuse.

• Students will use the distance formula to find the distance between two points.

• Students will practice these skills in their independent work.

Suggested Grades:

Seventh Grade - Eighth Grade - Ninth Grade - Tenth Grade - including Special Education students

Lesson Procedure:

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

Lesson Excerpt:

Introduction
In our last lesson, we learned about how to use the Pythagorean Theorem to find the distance from one point to another on a coordinate grid. Specifically, we were finding this measure for the hypotenuse of a right triangle. Today, we are going to learn how to use the distance formula to do this.

First, let's review what we have already learned.
When there is a right triangle graphed on a coordinate grid, we can use the distance between the points of the legs, and the Pythagorean Theorem to find the distance between the two points of the hypotenuse. Let's look at an example.

Using the Distance Formula
If we don't use the Pythagorean Theorem to find the length of the hypotenuse, we can also use the distance formula to find the length of hypotenuse. Here is the distance formula.

Continued...