Question

How do you find the radian measure of the central angle of a circle of radius 80 kilometers that intercepts an arc of length 160 kilometers?

Answer 1

`theta` = central angle = 2 radians

Explanation:

Use proportions, angles to arc length. Remember that a complete circle's arc length (circumference) = `2pir = 2pi80`

`theta/(2pi) = 160/(2pi80)` `or` `theta/1 = 160/(80) = 2`