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Circumference and Arc Length - Lesson 10-9

We started today by reviewing what we knew about the definition of circumference and the relationship between the circumference and the diameter of any circle:

Definition of the Circumference of a Circle

We then went over a couple of examples of using this knowledge:

Circumference Example 1

Circumference Example 2

Next, we defined arc length:

Definition of Arc Length

We then compared this to arc measure. Note that two arcs can have the same measure, but different lengths.

Arc Measure vs. Arc Length

We then used this information to do the following problems:

Arc Length Example 1

Arc Length Example 2

Arc Length Example 3

And summarized this work with the following theorem:

Theorem 97 - Arc Length

Before reviewing homework, we went through the following "cool" example:

Arc Length Example 4 - Question

The first challenge here was to get the correct diagram:

Diagram for Arc Length Example 4

Once we had that, we were OK...just use Theorem 98 and algebra!

Answer for Example 4

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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