Question

A circle has an arc of length 20π that is intercepted by a central angle of 180°. What is the radius of the circle?

Answer 1

10π

Explanation:

RULE: The angle measure of the central angle is congruent to the measure of the intercepted arc.

RULE: Central Angle = Arc length

Given:

Arc length (20 π) = central angle (180)

we know 180 degrees is a straight line, thus a semi-circle is created. This would be the diameter.

1/2 diameter is the radius. 20π/2 is the radius.

10π