Education Technology

# Activities

• ##### Subject Area

• Math: Geometry: Transformational Geometry

9-12

90 Minutes

• ##### Device
• TI-83 Plus Family
• TI-84 Plus
• TI-84 Plus Silver Edition

TI Connect™

• ##### Accessories

TI Connectivity Cable

• ##### Other Materials
This is Activity 2 from the EXPLORATIONS Book:
Exploring Mathematics with Cabri™ Jr. Application

## Rotations in the Plane

#### Activity Overview

In this activity, students will explore the properties of rotations and the relationships between the original and image figures.

#### Before the Activity

• Install the Cabri Jr. App on the students' graphing calculators using TI Connect™, a TI Connectivity cable and the unit-to-unit link cables
• See the attached PDF file for detailed instructions for this activity
• Print pages 19 - 28 from the attached PDF file for your class
• #### During the Activity

Distribute the pages to your class.

• Construct a rotation angle tool
• Construct a triangle and perform a rotation
• Investigate the relationship between the original triangle (the pre-image) and the new triangle (the image)
• Drag a vertex of the pre-image, a side of the pre-image, the entire triangle, center of rotation, and one of the radius points around the circle and explore the changes in the new triangle
• Understand which properties of the triangle are preserved by the rotation and which are not
• #### After the Activity

Students will fill in the Data Collection and Analysis sheet.

Review student results:

• As a class, discuss questions that appeared to be more challenging
• Re-teach concepts as necessary