# Angle at Centre

- Author:
- Joe Chung

10.2 Angles in a Circle
Angle at centre is two times the angle at the circumference.
(angle at centre 2 times angle at circumference)

1. Click and drag points C and D to adjust the angle at the centre.
What do you realize about the relationship between angle at the centre and angle at the circumference?
2. Click and drag point B to change the position of the angle at the circumference.
How does this affect the angle at the circumference?
3. Adjust the angle at the centre to 180 degrees.
What do you realize about the angle at the circumference?
4. Adjust the angle at the centre to greater than 180 degrees.
Does the relationship between angle at the centre and angle at the circumference still hold?