Education Technology

# Activities

• ##### Subject Area

• Math: Geometry: Circles

9-12

20 Minutes

• ##### Device
• TI-Nspire™ CX/CX II
• TI-Nspire™ CX CAS/CX II CAS
• TI-Nspire™
• TI-Nspire™ CAS
• ##### Software

TI-Nspire™
TI-Nspire™ CAS

3.2

## Exploring Circle Equations

#### Activity Overview

Students explore the equation of a circle. They will make the connection with the coordinates of the center of the circle and length of the radius to the corresponding parts of the equation. Then, students apply what they have learned to find the equation of the circles in several circular designs.

#### Key Steps

• Students will begin this activity by investigating the equation of a circle by moving the center of the circle. Students will then change the radius of the circle and determine what role the radius plays in the equation of the circle.

When students move the center of the circle or the radius the equation will change automatically.

• Students will apply what they have learned in Problem 1 to find the equations of circles in various designs.