Exploring Similarity
- Author:
- Jake Kubasta, dormanmath
A simple similarity guide for students.
Partners: ___________________ and _____________________
Period: ____
Steps for Geogebra Exploration Activity Today
1) Go to computechmath7.weebly.com
2) Click on Unit 4: Scale
3) Download the Student File
4) Measure the angles of both triangles and record them in the table below. To measure the angle, follow these steps:
a. Select the Angle tool
b. Click these points in the following order to measure the angles:
BAC, ACB, CBA then EDF, DFE, FED
Triangle ABC Triangle DEF
<(angle) BAC: <EDF:
<ACB: <DFE:
<CBA: <FED:
5) Move the slider (point n) to 3.0
6) Look at the lengths of the sides of the triangles on the screen. What are their lengths:
a:______ d’ ___________ b:_______ e:________ c:______ c’:_______
7) In one sentence write about what do you notice about the relationship between the sides of triangle ABC and their corresponding sides in triangle DEF?
________________________________________________________________________________________________________
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8) Write the x and y coordinates of point b:_______ and point e: _______
Now, move point B on triangle ABC to (0,0). Where is point E now? _______
9) Right click on point n and select ‘animate’. Observe the value of the angles and side lengths. Focus on the value of n, Write a sentence about the relationship between the value of n and the other side lengths.
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Part 2: Based on these explorations and Monday’s lesson, on a separate piece of paper, write a response to answer the following questions:
1.) Title the paper PART 2: SIMILAR TRIANGLES and include you name, date, and period.
2.) What do you need to know about the triangles to know if they are similar?
3.) Will this rule of similarity work with non-triangles? How do you know?
4.) How does this project help you understand problems involving similar triangles?
5.) If you have time, try the Pentagon exploration activity also on the website!