6. Area of a circle

Area of a circle

A circle 

A closed line consisting of all points on the plane that are equidistant from a given point on the plane is called a circle.
Area of circle = πr², where r is the radius of the circle.
Diameter of Circle:

The distance across the circle. The length of any chord passing through the center. It is twice the radius.
Diameter = 2⋅Radius = 2r

Radius of circle:
The radius is the distance from the centre to any point on the circle.
Radius is also known as half  of the diameter.
Radius=Diameter/2

Area of the Circle:
The area of a circle is the number of square units inside that circle.
Area of the Circle = πr2 sq.units
Here r is the radius of the circle.
The value of the π [pi] can be either 22/7 or 3.14.