exercise: circle sector problem 3
A circular sector has central angle of 170° and an arc length of 15 m.
a) calculate the radius
b) calculate the the perimeter/circumference of the circle sector
c) calculate the the area of the circle sector
answer: circle sector problem 3
a) answer radius:
arc length = d * π * α : 360
15 = d * π * 170 : 360 / * 360
5 400 = d * π * 170 / : 170
31.76… = d * π / : π
10.11 = d / : 2
r = 5.06 m
A: The radius is 5.06 m.
b) answer perimeter:
perimeter = 2 * radius + arc length
perimeter = 2 * 5.06 + 15
perimeter = 25.12 m
A: The perimeter of the circle is 31.81 meters.
c) answer area:
area = r² * π * α : 360
area = 5.06² * π * 170 : 360
area = 37.98 m²
A: The area of the circle is 37.98 m².