Tangents from External Point
1. Click and drag point A.
What do you observe about the lengths AB and AC?
What do you observe about the angles OAC and OAB?
What do you observe about the angles AOC and AOB?
Tangents from External Point
If two tangents are drawn from an external point to a circle, then
- the lengths of the tangents are equal, the line joining the external point and the centre of the circle bisects the angle between the tangents.