Activities

Download
- Download All Files (ZIP)
- Before the Activity Files
- CabriGeo_II_Plus_Act03.fig
Alignment
- Standards Alignment
- Textbook Alignment
Subject Area
- Maths: Geometry: Similarity and Proportion
- Maths: Geometry: Triangles
Author

Jean-Marie Laborde and Frank Bellemain
Level

9-12
Activity Time

15 Minutes
Software

Cabri Geometry™
Report an Issue

Looks Right

Activity Overview

Students use the Cabri Geometry II Plus software to determine which given triangle retains its basic shape after its vertices are dragged around the screen.

Before the Activity

Download the Cabri Geometry™ software on the computer

See the attached FIG file for details of this activity

During the Activity

Follow the Activity procedure:

Drag the vertices of the first triangle (figure A) around the screen

Observe that along with the angles, the shape also changes

Drag the vertices of the second triangle (figure B) around the screen

Notice that the size of the triangle changes, but segment GD is always perpendicular to segment DE

After the Activity

Review student results:

As a class, discuss questions that appeared to be more challenging

Re-teach concepts as necessary

Control your cookie preferences

You can control your preferences for how we use cookies to collect and use information while you're on TI websites by adjusting the status of these categories.

Category	Description	Allow
Analytics and performance cookies	These cookies, including cookies from Google Analytics, allow us to recognize and count the number of visitors on TI sites and see how visitors navigate our sites. This helps us improve the way TI sites work (for example, by making it easier for you to find information on the site).
Advertising and marketing cookies	These cookies enable interest-based advertising on TI sites and third-party websites using information you make available to us when you interact with our sites. Interest-based ads are displayed to you based on cookies linked to your online activities, such as viewing products on our sites. We may also share this information with third parties for these purposes. These cookies help us tailor advertisements to better match your interests, manage the frequency with which you see an advertisement, and understand the effectiveness of our advertising.
Functional cookies	These cookies help identify who you are and store your activity and account information in order to deliver enhanced functionality, including a more personalized and relevant experience on our sites. If you do not allow these cookies, some or all site features and services may not function properly. If you do not allow these cookies, some or all of the site features and services may not function properly.
Social media cookies	These cookies allow identification of users and content connected to online social media, such as Facebook, Twitter and other social media platforms, and help TI improve its social media outreach.
Strictly necessary	These cookies are necessary for the operation of TI sites or to fulfill your requests (for example, to track what items you have placed into your cart on the TI.com, to access secure areas of the TI site, or to manage your configured cookie preferences).	Always On

Category

Description

Allow

Analytics and performance cookies

These cookies, including cookies from Google Analytics, allow us to recognize and count the number of visitors on TI sites and see how visitors navigate our sites. This helps us improve the way TI sites work (for example, by making it easier for you to find information on the site).

Advertising and marketing cookies

These cookies enable interest-based advertising on TI sites and third-party websites using information you make available to us when you interact with our sites. Interest-based ads are displayed to you based on cookies linked to your online activities, such as viewing products on our sites. We may also share this information with third parties for these purposes. These cookies help us tailor advertisements to better match your interests, manage the frequency with which you see an advertisement, and understand the effectiveness of our advertising.

Functional cookies

These cookies help identify who you are and store your activity and account information in order to deliver enhanced functionality, including a more personalized and relevant experience on our sites. If you do not allow these cookies, some or all site features and services may not function properly.

Social media cookies

These cookies allow identification of users and content connected to online social media, such as Facebook, Twitter and other social media platforms, and help TI improve its social media outreach.

Strictly necessary

These cookies are necessary for the operation of TI sites or to fulfill your requests (for example, to track what items you have placed into your cart on the TI.com, to access secure areas of the TI site, or to manage your configured cookie preferences).

Always On

Download

Before the Activity Files

Alignment

Subject Area

Author

Level

Activity Time

Software