Education Technology

# Activities

• ##### Subject Area

• Math: Geometry: Triangles

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 16 from the EXPLORATIONS Book:
Cabri™ Jr.: Interactive Geometry Activities and Investigations.

## Midsegments of a Triangle

#### Activity Overview

In this activity, students will construct midsegments of a triangle, and look to formulate statements that appear to be true about the construction. They will form a midsegment triangle and compare the properties of the triangles formed.

#### 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 Cable
• Use the TI-Navigator™ to transfer the attached Cabri Jr. AppVar files to each calculator
• See the attached PDF file for detailed instructions for this activity
• Print pages 101 - 102 from the attached PDF file for your class
• #### During the Activity

Distribute the pages to your class.

Follow the Activity procedures:

• Use the AppVar to go directly to the exploration section
• Construct a triangle and one of its midsegments
• Use measurement tools (Distance and length, angle, and slope) to explore the relationship between the triangles formed
• Construct the other two midsegments of the triangle
• Compare the area and the angles of the four interior triangles formed
• #### After the Activity

Review student results:

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