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Angles Related to a Circle - Lesson 10-5

Today we by reviewing a couple of definitions (angles with vertices on the circle):

Inscribed Angle Definition

Tangent-Chord Angle Definition

We then learned a property of these types of angles:

Theorem 85 - Measure of an Inscribed Angle

Next, we defined chord-chord angles (angles with vertices inside the circle):

Chord-Chord Angle Definiiton

And learned a property about them:

Theorem 86 - Measure of chord-chord angle

Here's a hint for how to prove Theorem 86...see if you can do it!

Theorem 86 Proof Hint

We then defined three more types of angles related to circles (those with their vertices outside of the circle and learned a property about them:

Measures of Secant-Secant, Secant-Tangent Angles

Here's a summary of the information shown above:

Arc Angle Summary

We finished by doing the following example and then started on homework:


Other Links
Class Notes
Lesson 10-1
Lesson 10-2
Lesson 10-3
Lesson 10-4
Lesson 10-5
Quiz Topics
Lesson 10-6
Lesson 10-7
Lesson 10-8
Lesson 10-9
Test Topics
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