1. 7-6 Circles & Arcs 7-7 Area of Circles and Sectors

2. Vocabulary

4. Central Angle – angle whose vertex is the center of the circle <BAF, <FAE

5. Vocabulary & Formulas Concentric Circles – circles that have same center. Circumference – distance around circle C = 2  r or C = d  Area A =  r 2

6. Length of an Arc: what’s the formula?

7. Formulas Measure of an arc is always in degrees measure of arc = central angle Arc Length is always in dimensions 2  r

8. Area of Sector: What is the formula?

9. Formula Area of a Sector A =  r 2

10. Formula Area of a segment 1)Find area of Sector 2)Find area of Triangle 3)Area of Segment = area of sector minus area of triangle

11. Examples

12. 1)If KJ = 5 find the area of circle K. 2)If = 120 and KL = 6, what is the area of sector JKL? 3) If m<JKL = 135 and KJ = 2, what is the area of sector JKL?

13. Examples: Find area of segment.