Answer:
2 radians
Explanation:
the arc length is calculated as
arc = circumference of circle × fraction of circle
let x be the central angle , then
arc = 2πr ×
( cancel 2π on numerator and denominator )
= 2r × x
given arc length = 40 , then
2 × 10 × x = 40
20x = 40 ( divide both sides by 20 )
x = 2
the central angle has a measure of 2 radians