Education Technology


Inscribed Angles Intercepting The Same Arc

Activity Overview

Students investigate the properties of angles inscribed in a circle. They use the drawing and measurement tools of Cabri™ Jr. to draw and measure certain angles, and establish the relationship between angles that intercept the same arc. NCTM Geometry Standard covered: Analyze characteristics and properties of 2- and 3-dimensional geometric shapes and develop mathematical arguments about geometric relationships.

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
  • Set up the TI-Navigator™ system
  • See the attached PDF file for detailed instructions for this activity
  • Print pages 41-43 from the attached PDF file for your class
  • During the Activity

    Distribute the pages to your class.

    Follow the Activity procedures:

    • Draw a circle
    • Mark two points on the circle to determine an arc
    • Draw segments that will form the sides of the inscribed angles
    • Mark two points to be the vertices of inscribed angles
    • Observe the relationship between the inscribed angles
    • Explore other inscribed angle pairs by changing length of arc and vertices

      TI-Navigator activity:
    • Use Screen Capture to check students' progress

    After the Activity

    Review student results:

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