Education Technology

Arcs and Angles - Using Cabri Jr. to explore inscribed and central angle properties in circles

Published on 06/09/2008

Activity Overview

This activitie uses the power of Cabri Jr. to explore the relationship between inscribed angles and central anlges in cirles.

Before the Activity

Print out and copy the word document. Student will draw a circle, construction central and inscribed angles. The students will measure the angles and drag the angles around the circle and obsevre the result. This should lead to the conjecture that inscribed angles measure 1/2 fo the cental angle.

During the Activity

More inscribed angles can be add to the circle and explored. Many problems in geometry text books have multiple inscribed angles. Adding more angles can make the construction look more like homework problems

After the Activity

Review student answers:

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