1. Circles: Arc Length and Sector Area
Know and apply properties of a circle to solve problems and logically justify results.

2. Guiding Question: How can I find part of a circumference or part of a circle?
Lesson Obj: IWBAT find an arc length or sector area of a circle.
Recall Circles
Definition of a circle
Radius
Diameter
Circumference
Area

3. Guiding Question: How can I find part of a circumference or part of a circle?
Parts of a circle
How do you calculate circumference? What if I only wanted part of that?

4. Guiding Question: How can I find part of a circumference or part of a circle?

5. Guiding Question: How can I find part of a circumference or part of a circle?
To solve divide the angle by 360 and multiply by the circumference.
Calculate the arc length of this circle.

6. Guiding Question: How can I find part of a circumference or part of a circle?
Arc Length
Sector Area
Finding part of the circumference
Never looking inside the circle
No area only length (label is not squared)
Finding part of the area of a circle
Only looking inside the circle
Answer is an area, should be squared

7. Guiding Question: How can I find part of a circumference or part of a circle?
For an arc
= 𝜃 360 2𝜋𝑟
For a sector area
= 𝜃 360 𝜋 𝑟 2

8. Find the sector area in this problem
Guiding Question: How can I find part of a circumference or part of a circle?
Find the sector area in this problem
Find the area here.

9. Guiding Question: How can I find part of a circumference or part of a circle?
Assignment: Arc length and Sector Area packet