# How to Find the Radius from the Area

## Finding the Radius from the Area

The radius of a circle is found from the area of a circle using the formula:

In this formula, **A** is the area of the circle. The image below shows what we mean by finding the radius from the area:

## How to Find the Radius from the Area

Finding the radius from the area is easy.

### Question

What is the radius of the circle, with area 10 cm^{2}, below?

### Step-by-Step:

# 1

Start with the formula:

Radius = √ (^{A}⁄_{π})

**Don't forget:** √ means square root, / means ÷ **and** π is pi (≈ 3.14)

# 2

Substitute the area into the formula. In our example, A = 10.

Radius = √ (^{10}⁄_{π})

Radius = √ (10 ÷ π)

Radius = √ (10 ÷ 3.14)

Radius = √ 3.18

Radius = 1.78 cm

### Answer:

The radius of the circle is 1.78 cm.