12.2: Distances in the Coordinate Plane
This activity is intended to supplement Algebra I, Chapter 11, Lesson 5.
In this activity, you will explore:
- finding the length of a segment using the Distance Formula
- finding the length of a segment using the Pythagorean Theorem.
Problem 1 – The Distance Formula
Construct a segment. Find the coordinates of the endpoints and the measured length. Use the distance formula to calculate the length.
Endpoints | Measured Length | Calculated Length |
---|---|---|
(_____ , _____) and (_____ , _____) | ______________ | ______________ |
(_____ , _____) and (_____ , _____) | ______________ | ______________ |
What is important to remember when using the Distance Formula?
What happens to the Distance Formula when your segment is horizontal or vertical? Give an example using endpoints.
(_____ , _____) and (_____ , _____)
Problem 2 – The Distance Formula and the Pythagorean Theorem
Find the length of all three sides of your triangle. Which side is the longest? Can two of the sides be equal lengths? Which two?
Use the Pythagorean Theorem to calculate the length of your segment in another way.
Endpoints | Measured Length | pythagorean Length |
---|---|---|
(_____ , _____) and (_____ , _____) | ______________ | ______________ |
(_____ , _____) and (_____ , _____) | ______________ | ______________ |
What is the relationship between the Pythagorean Theorem and the Distance Formula?
Problem 2 - Apply The Math
What formula gives the distance between the points and ?
Determine the length of the segment with the following endpoints:
1. and
2. and
3. and
4. and
5. and
6. and
Given an endpoint and a length of a segment, find a possible other endpoint:
7. Endpoint: ; Length