Education Technology

# Activities

• ##### Subject Area

• Math: Geometry: Points, Lines and Angles
• Math: Geometry: Triangles

6-8
9-12

80 Minutes

• ##### Device
• TI-Nspire™
• TI-Nspire™ CAS
• ##### Software

TI-Nspire™
TI-Nspire™ CAS

• ##### Other Materials
TI-Nspire, cardboard, scissors, pencil, straight edge

## Balancing Act

#### Activity Overview

Students will explore the centriod of a triangle. They will discover that it is the center of gravity. They will balance a cardboard triangle on the end of a pencil. Then they will construct the medians with folds and pencil. After students have seen that the center of gravity is the point of concurrency of the three medians, they will use their TI-Nspire™ to explore more. They will discover segment length relationships as well as area relationships around the centroid.

#### Before the Activity

Students should be familiar with median line. They have had an introduction to paper folding constructions.

Send students the file BalancingAct.tns

#### During the Activity

Walk around and assist students. Take pictures of students balancing triangles.

#### After the Activity

This is a part of a unit on triangle centers. Also students may try to find centers of gravity for other polygons.