a circle has a circumference of 20. It has an arc of length 9/2. What is the central angle of the arc in degrees?

Mathematics · High School · Tue Nov 03 2020

Answered on

Formula :

Length of arc = θ/360 × 2πr 

Length of arc = 9/2

Circumference of circle, 2πr = 20

9/2 = θ/360 × 20

θ = 9 × 360/2×20

= 81°

 

Hence, central angle of arc is 81°.