2. Essential Understanding
You can find the area of a circle when you know its
radius. You can use the area of a circle to find the
area of a circle formed by two radii and the arc the
radii when they intersect with the circle
Students will be able to find the areas of circles,
sectors, and segments of circles
3. Area of a Circle
A = πr2
What is the area of circular wrestling region with a
42 ft diameter?
What is the area of a circular ice skating rink with a
radius of 24 ft?
4. Area of a Sector
Sector of a circle: region bounded by an arc of the
circle and two radii to the arc’s endpoints.
A circle has radius of 4 in. What is the area of a sector
bounded by a 45° minor arc? Leave your answer in
terms of π.
5.
6. Segment of a Circle
Part of a circle bounded by an arc and the segment
joining its endpoints.
To find the area of a segment for a minor arc, draw
radii to form a sector. The area of the segments
equals the area of the sector minus the area of the
triangle formed
7. Finding Area of a Segment
What is the area of the shaded segment shown
below? Round your answer to the nearest tenth.