Many real-world applications of geometry are represented with circles and geometric relationships found within circles. In astronomy, many orbits and planetary features are roughly circular, so scientists need to be able to calculate angle measures between parts of circles. The Barringer Crater in Arizona is an example of a nearly circular feature studied by astronomers.

Given the following image, click on the name of the correct segment, line, angle or arc. Use a Snipping Tool to copy and paste your completed image into your notes.

Before continuing, please review the definitions for chords, secants, and tangents.