## What is circle?

Introduction of Circle & Area & Circumference | CIRCLE is a closed shape figure which has some constant distance from the from any fixed point, which is known as the Centre of Circle. The distance between center to any point of a circumference of a circle is known as Radius and the twice of the radius is known as the diameter of that circle. Circumference of a circle is known as the distance around the circle. Here, you will know detailed knowledge of **Area & Circumference of circle.**

### What is pie (π)?

Pie is the number you get when you divide the circumference by the diameter. The value of pie we will get it will be 3.141592654.

### Circumference Of Circle

Circumference is the distance around the circle.

Circumference = 2πr or 2d

where

“r” is the radius of a circle.

“d” is the diameter of a circle.

**Example:** Find the circumference whose radius is 4 c.m

**Solution:**

r = 4 c.m

**Circumference = 2πr**

= 2 x 3.14 x 4

Circumference is 25.12 c.m

**Area of Circle**

Area = πr^{2}

**Area of a circle by diameter**

Area = πr^{2}

=π x (*d*2)^{2}

**Area = π d^{2}4**

**Example: –**

**Find the Area of Circles which has radius 2 cm, 10 m, 23 mm and 78 cm.**

**Find the area of a circle with the help of diameter.**

### Tangent

Tangent is the line which touches the outer part of the circle.

### Secant

A line which cuts the circle from their opposite point known as Secant.

### Chord

The chord is the line, whose points lie on the circumference of a circle.

We can understand chord, secant, tangent, diameter & radius, all in one frame just by seeing the image given below

I hope this, the article will help you to understand the concept of **Introduction of Circle | Area | Circumference**. If you have any question related to the article, you can post it into the comment section. You will get a reply shortly.

I hope you have learned it properly.