# Area of an Ellipse(KS3, Year 7)

## The Lesson

The area of an ellipse is found using the formula: In this formula, a is the semi-minor axis and b is the semi-major axis. The image below shows what we mean by the semi-minor and semi-major axis: ## How to Find the Area of an Ellipse

Finding the area of an ellipse is easy.

## Question

What is the area of an ellipse with a semi-minor axis of 3 cm and a semi-major axis of 5 cm, as shown below? # 1

Area = πab
Don't forget: π is pi (≈ 3.14) and πab = π × a × b

# 2

Substitute the semi-minor and semi-major axis into the formula. In our example, a = 3 and b = 5.
Area = π × 3 × 5 = 47.1 cm2

The area of the ellipse with a semi-minor axis of 3 cm and a semi-major axis of 5 cm is 47.1 cm2.

## "Find the Area" Widget

Here is a widget to help you learn the formulas to find the areas of different shapes.  ## Lesson Slides

The slider below shows another real example of how to find the area of an ellipse. Open the slider in a new tab

## What Is an Ellipse?

An ellipse is a squashed circle. It is symmetrical about its longest axis (called the major axis) and its shortest axis (called the minor axis). Half of the major axis is the semi-major axis. Half of the minor axis is the semi-minor axis. Help Us To Improve Mathematics Monster