1. Exact Area and Circumference of Circles
Section 10.2a

2. Warm Up
Find the area and circumference of each circle. Round the nearest hundredth.
r = 4in
d = 16 in

3. Find the exact area and circumference of each circle.
r = 2in
d = 10 in

4. Equation of a Circle: Find the exact area of each circle:
(x+4)2 + (y-2)2 = 169
(x+2)2 + (y – 1)2 = 30
(x-4)2 + (y+2)2 = 24

5. To find the exact area of a sector of a circle:
𝑑𝑒𝑔𝑟𝑒𝑒𝑠 360 (𝐴𝑟𝑒𝑎 𝑜𝑓 𝐶𝑖𝑟𝑐𝑙𝑒)

8. Find the exact circumference of the circle if:
A = 49 π ft2
A = 20 π in2
A = 25 m2
A = 5 m2

9. Find the exact area of the circle if:
a. C = 12 π in
b. C = 17 π in
c. C = 24 in
d. C = 9 in

10. Find the exact area of each shaded region: