1. Mrs. McConaughyGeometry1 Any Way You Slice It: Calculating the Areas of Circle Portions sectors, segments, and annuli During this lesson, you will solve problems involving the areas of the following circle portions: sectors, segments, and annuli.

2. Mrs. McConaughyGeometry2 Before we start, recall:RadiusDiameterCircumferenceArea 5m 5m 14 in. 18 π yd. 121π m 2 AREA (circle) = π r 2

3. Mrs. McConaughyGeometry3 Before we start, recall: Annulus Annulus- ________________ _______________________ region between two concentric circles AREA (annulus) = π R 2 - π r 2

4. Mrs. McConaughyGeometry4 Sector Sector- _______________________________ _____________________________________ VOCABULARY region between an arc and two radii of a circle AREA (sector) = arc/360 π r 2 40 9 cm

5. Mrs. McConaughyGeometry5 Segment Segment- ______________________________ _____________________________________ VOCABULARY region between a chord and an arc of a circle AREA (segment) = Area (sector) - Area (triangle ) 6 cm

6. Mrs. McConaughyGeometry6 Final Checks for Understanding 1. Define and illustrate the following circle portions: sector, segment, and annulus. 2. Write formulas for the following circle portions: sector, segment, and annulus.

7. Mrs. McConaughyGeometry7 HOMEWORK ASSIGNMENT: CIRCLE PORTIONS WS