Education Technology

# Activities

• ##### Subject Area

• Math: Geometry: Circles

9-12

50 Minutes

• ##### Device
• TI-89 / TI-89 Titanium

## Chords, Secants, and Tangents

#### Activity Overview

Students construct chords, secants, and tangents. From those constructions they develop a deeper understanding of the terms, as well as explore certain properties of the constructions.

This Activity comes from SIMMS Integrated Mathematics Level 2, © Kendall/Hunt Publishing Company.

#### Before the Activity

Print the CircleParts.SE.pdf file and the CirclePartsTemplate.pdf for each student.

Print a teacher copy of the CircleParts.TE.pdf file, as it provides sample answers to the questions posed.

#### During the Activity

In the Exploration, students will use the TI-89 calculator and The Geometer's Sketchpad® App to construct chords, secants, and tangents. Those constructions will help them more fully understand the definitions of those terms.

In Discussion 2, the students will use their new information to explore properties of these constructions. For Part d, each student will need a copy of the CirclePartsTemplate.pdf file.

The Exploration can be done individually or in pairs. Discussion 2 can be done individually, in small groups, or assigned as homework.

A whole class discussion of student responses is helpful to ensure students fully understand the mathematics involved.

#### After the Activity

Review student results:

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