Question

What is the measure of θ in radians?

Enter an exact expression.

In the diagram, θ is a central angle.

Answer 1

pi

Explanation:

Arc length = r × theta

8pi = 8 × theta

theta = 8pi/8

= pi radians

Answer 2

pi

Explanation:

Theta is 1/2 of a circle

A circle is 360 degrees or 2pi radians

Take 1/2 of that for a semi circle

180 degrees or pi radians