### Circle

A circle is a particular shape of the objects. A circle is a type of closed shape. It is the set of all points in a plane that are at a given distance from a given point. So, it is the curve traced out by a point that moves in a plane in such a way so that its distance from the given point is constant.

Where,

r the radius of the circle.

d the diameter of the circle.

C circumference of the circle.

### Diameter of the Circle

D = 2 × R

### Circumference of the circle

C = 2 × π × R

### Example:

Find the circumference of a circle whose radius is 10 cm.

### Solution:

Circumference, C = 2πr

= 2 ×3.14×10

= 62.8 cm

### Area of the circle:

A = π × R^{2}

### Example:

Find the area of a circle whose radius is 10 cm

### Solution:

Area = 3.14 × 10^{2}

= 314 cm^{2}