The radius of a circle is 20 kilometers. What is the angle measure of an arc bounding a sector with area 10​𝜋 square kilometers?

Answer 1

Area of a circle is pi(r^2). If the radius is 20 km, the area of the circle is 400pi

if the area of a sector is 10pi, then the angle is A where A/2pi = 10pi/400pi

A = 10pi/200pi = 1/20 radians