Topic Consolidation: Geometrical Properties of Circles

Chord- lines by joining two points on a circle
Tangent- line touching the circle at its circumference at only 1 point
Secant- An extended chord on one side

Chord Properties
1. If the radius cuts the chord into half, then the radius is perpendicular to the chord. (and vice versa)

Tangent Properties
1. The radius is perpendicular to the tangent at the point of tangent.

Angle properties of circle
1. Angle at center = 2x angle at circumference
2. Angles in the same segment are equal
3. Angle in a semi-circle is 90 degrees
4. Opposite angles of a cyclic quadrilateral add up to 180 degrees.
5. Exterior angles of a cyclic quadrilateral is equal to its interior opposite angle