exercise: circle sector problem 2
A circular sector has a central angle of 124° and an area of 44,82 cm²
a) calculate the radius
b) calculate the arc length
c) calculate the the perimeter/circumference of the circle sector
answer: circle sector problem 2
a) answer radius
44.82 = r² * π * 124 : 360 / * 360
16 135.20 = r² * π * 88 / : 88
183.45… = r² * π / : π
58.36 = r² / √
r = 7.64 cm
A: The radius is 7.64 cm.
b) answer arc length
diameter (d) = 2 * 7.64 ⇒ 15.28 cm
arc length = d * π * α : 360
arc length = 15.28 * π * 124 : 360
arc length = 16.53 cm
A: The arc length is 16.53 centimeter.
c) answer perimeter
perimeter = 2 * radius + arc length
perimeter = 2 * 7.64 + 16.53
perimeter = 31.81 cm
A: The perimeter of the circle is 31.81 centimeter.