Arcs of Circles
Arc of a Circle
An arc is a part of a circle. In the figure, AB is an arc of the circle P.
Arc AB is denoted by AB.
There is a difference between a circle and a circular region. A circular region is union of circle and its interior.
Semicircle
A diameter divides a circle into two equal parts. Each part is called semicircle or half circle. We use three letters to name a semicircle. The first and third letter are end points of diameter.
In the figure, XAY is semicircle. Can you name the other semicircle?