5.1a Circles
5.1.1 Parts of a Circle
1. A circle is set of points in a plane equidistant from a fixed point.
2. Parts of a circle:
(a) The centre, O, of a circle is a fixed point which is equidistant from all points on the circle.
(b) A sector is the region enclosed by two radii and an arc.
(c) An arc is a part of the circumference of a circle.
(d) A segment is an area enclosed by an arc and a chord.
