Key learning points

1. Circle theorems can be used in situations involving circles
2. It is not always obvious that a circle theorem can be used
3. Sometimes you may wish to add more to a diagram in order to deduce more information

Keywords

• Tangent - A tangent of a circle is a line that intersects the circle exactly once.

• Chord - A chord is any line segment joining two points on the circumference of a circle.

• Perpendicular - Two lines are perpendicular if they meet at right angles.

• Equidistant - Points A and B are equidistant from a third point C if the distance AC is equal to the distance BC.

Common misconception