1. 11.5 – Areas of Circles and Sectors

2. Area of a Circle: A=  r 2

3. Area of a Sector: Area between two radii in a circle

4. 1. Find the area of the circle. A=  r 2 A=  (7) 2 A= 49  cm 2

5. 1. Find the area of the circle. A=  r 2 A=  (6.5) 2 A= 42.25  in 2

6. ( ) 2. Find the area of the shaded figure. A = +  r 2 2 +bh A =  (2) 2 2 +(4)(4) 4 4 4 A = 4  2 +16 A = 22 +16ft 2

7. ( ) 2. Find the area of the shaded figure. A =– 8in 4in r2r2 A = –s2s2  (4) 2 A = –(8) 2 16  A = –64 16  A = – 64in 2 8in

8. 3. The area of a circle is 58 square inches. Find the diameter. Round to two decimal places. A =  r 2 58 =  r 2 18.46 = r 2  4.30in = r d = 8.59in

9. 4. Find the area of sector formed by  ACB. Round to two decimal places. Leave answers in terms of pi. 360x = 6000 

10. 360x = 40000  x = 11.11  m 2 5. Find the area of sector formed by  PSQ. Round to two decimal places. Leave answers in terms of pi.

11. 6. Find the area of sector formed by  ACB. Round to two decimal places. Leave answers in terms of pi. 360x = 7040  110°

12. 360x = 7050  282° 7. Find the area of sector formed by  PSQ. Round to two decimal places. Leave answers in terms of pi.