Kindergarten
Grade One
Grade Two
Grade Three
Grade Four
Grade Five
Grade Six
Grade Seven
Grade Eight
Grades Nine - Twelve
 
<<Back To Grades 9-12 Units/Lesson Plans

Distance Formula 

Designed by: Melanie B. Moorer    School: Dreher High School 

Grade Level: 9-10    Subject: Mathematics (Geometry)

Core Curriculum Objective: Apply the distance formula.

Overview: Students will work independently and in small groups to develop strategies to find distance and apply their knowledge in everyday situations. Students will use various instructional strategies such as: demonstrations, presentations, critical thinking, and deduction. As a culminating assessment, students will use a blue print of the school sectioned off in coordinates to measure the distance from the classroom to the closest exit of the building in order to determine the quickest exit in case of an emergency. 

Purpose/Essential Question(s): How do you find distance? 

Time Frame: This lesson is designed for two ninety-minute class periods. 

Resources and Instructional Materials:

Geometry: An Integrated Approach 
D. C. Heath and Company 
Lexington, Massachusetts / Toronto, Ontario 
Pages 71-76 

Transparencies 

Overhead Projector 

Blue print of school building

Rulers 

Calculators 



Day One 

Bell- Work: (work to be done when the student enters the class before the tardy bell) 

Have students copy the following formula for distance off a ready-made transparency: 

 

Motivating the lesson: 
Draw the figure below on a transparency. Write below it: How many different routes can be traced from point A to point B if the movements must be to the right or down? 

 

Answer: 36 



Work through the following teacher-led examples: 

1.Let A = (-2, 5) and B = (4, 1). Find the distance between the two points using the distance formula. 

2. On a city map, the streets are 100 feet apart horizontally and 250 feet apart vertically. On a coordinate plane where the capital building is at the origin, north is directing up the positive y-axis, south is directing down the negative y - axis, east is directing right on the positive x - axis, and west is directing left on the negative x - axis, find the walking distance from the City Hall (1, 2) to the Riverfront Park (-2, 3). Then find the distance as a bird would fly (directly from each point - using the distance formula) 

Activity One: 
Have students work independently on Worksheet A for 15 minutes. Then let the students get with their partner (already selected by the teacher when designating collaborative pairs) compare work and reach a consensus on what the correct answers are. After another ten minutes, randomly select student pairs to come up and find distances on the overhead for the class to see. 

For homework, give the students some problems similar to those on Worksheet A. 


Day Two 

Allow students to go over their homework problems by comparing answers with 
their partners. The teacher will ask for any questions and go over any problems the students may still be having trouble with. 

Activity Two 
Pair students with a partner. Students will receive Culminating Activity Sheet and the rubric for this lesson. In this activity, the students will demonstrate their ability to find distances by finding the closest exit out of the building in case of an emergency. The teacher will demonstrate how to draw a coordinate plane on the blue print of the school building. The students will then follow the steps on the sheet in order to find the distance from the classroom to the closest exit of the building. The teacher will evaluate the culmninating assessment with the following rubric: 

 

Culminating Activity Excellent
25-18
Acceptable
17-14
Unacceptable
13-0
Coordinate Plane Drawn Correctly Coordinate plane drawn neatly with correct origin Coordinate plane drawn neatly without correct origin Coordinate plane not drawn neatly without correct origin 
Points Labeled Correctly Both points labeled correctly One point labeled correctly  No points labeled correctly 
Correct Distance Formula Used Correct distance formula used  Incorrect distance formula used
Calculations Calculations are correct and work is shown  Calculations are correct but no work is shown  Calculations are incorrect 


 
  

Worksheet A 
Finding Distance Date

(Click here for a printable Adobe Acrobat version of this page)

Name________________________________________________________

Date__________________________________________

Find the distance between the two points. Use you calculators for those that do not come out as perfect square roots. Round your answers to two decimal places. 

1. A = (4, 3) and B = (-2, -5) 

2. C = (-4, 1) and D (6, -1) 

3. E = (-3, 3) and F = (5, -1) 

4. G = (2, 8) and H (4, 8) 

5. I = (5, 9) and J = (5, -2) 

6. K = (2.5, 3.6) and L = (7.4, 3.2) 

7. M = (0, 4) and N = (8, 0) 

8. O = (0, 0) and P = (-3,-6) 

9. Q = (-I, 4) and R = (3, -1) 

10. S = (8,7) and T = (5,-3) 




Culminating Activity for the 
Distance Formula 
(Click here for a printable Adobe Acrobat version of this page)

 

Materials Needed: Blue print of school building, Ruler, Calculator

Procedures: 

1. Meet with your partner and begin to draw the coordinate plane as instructed by the teacher. 

2. Design your coordinate plane so that the main off ice of the school is at the origin. 

3. Find the doorway to the classroom and the closest exit to the classroom. Label each of these points on the blue print as follows: 

a. The doorway to the classroom = C 
b. The closest exit = E 
c. Main Office= O 

4. Draw straight lines down hallways and staircases (if needed) beginning at the doorway to the classroom and ending at the exit. 

5. Find the distance from the classroom to the nearest exit by finding the distances of each of the line segments drawn. 

6. On the back of the blue print, make sure to show all your work when using the distance formula! 

**Make sure you put your name and your partner's name on the back of the blue print! You'll be presenting these to the class, so be familiar with your results and how you got them. 

copyright 2002  Richland County School District One