# Equation of Circle Calculator

## What is Equation of the Circle Calculator?

'Cuemath's Equation of Circle Calculator' is an online tool that helps to calculate the equation of the circle. Cuemath's online Equation of Circle Calculator helps you to calculate the equation within a few seconds.

## How to Use Equation of Circle Calculator?

Please follow the below steps to find the equation of the circle:

• Step1: Enter the centre and radius of the circle in the given input box.
• Step 2: Click on the "Solve" button to find the equation of the circle.
• Step 3: Click on the "Reset" button to clear the fields and find the equation of the circle for the centre and the radius of the circle.

## How to Find Equation of Circle?

The circle is defined as the set of points placed at an equal distance from a single point in a plane. The midpoint of the circle is called the centre of the circle. The distance from the centre of the circle to the surface is called the radius(r). The equation of the circle is calculated using the formula:

Equation of circle: (x - x1)2 + (y - y1)2 = r2, where (x, y) are points on surface of circle, (x1, y1) are coordinates of centre, and 'r' is radius of the circle.

### Solved Example:

Find the equation of the circle with centre (3, 2) and radius is 5 units

### Solution:

Equation of circle: (x - x1)2 + (y - y1)2 = r2,

(x - 3)2 + (y - 2)2 = 52

(x - 3)2 + (y - 2)2 = 25.

Therefore, equation of circle is (x - 3)2 + (y - 2)2 = 25.

Similarly, you can try the calculator to find the equation of circle for

1) centre (5,2) and radius = 7 units

2) centre (-4,-1) and radius = 9 units