Geogebra: Chord Properties
Lesson 9.2 • Chord Properties In this lesson you will discover some properties of chords, arcs, and central angles. Investigation 1: Chords and Their Central Angles
Drag different parts of your figure to confirm that the chords you constructed stay congruent.
1. Measure central angles CAB and DAE. Fill in the blank for question #A
2. Measure the ARC intercepted by the each chord. What can you conclude about congruent CHORDS in a
circle and the arcs they intercept? Fill in the blank for question #B.
Question A
Chord Central Angles Conjecture: If two chords in a circle are congruent, then their central angles are ___________.
Question B
Chord Arcs Conjecture: If two chords in a circle are congruent, then their _________________ are congruent.
Prove the statement "If arc ED is congruent to arc CB, then segment ED is congruent to segment CB" Hint: Use the fact that if arcs are congruent, their central angles are congruent. Also, remember, that all radii of a circle are congruent.
