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Maths Learn & Test Study Notes

Area

📖Definition

The Area of a shape is the amount of space it takes up. You need to know how to work out the area of a few basic 2D shapes. With this knowledge you'll be able to work out the area of more complex shapes.

Rectangle

The Area of a Rectangle with sides lengths a, b is ab

Triangle

The Area of a Triangle is given by the formula 1/2 Base x Perpendicular Height

Diagram

area of a triangle

Compound Shapes

Compound Shapes are made up of a number of smaller, simpler shapes.
The key is to break the shape down into its constituent parts, work out the area of each part and then sum the areas up.

💡Tips/hints

It's a good idea to draw a diagram showing the constituent smaller shapes.

✏️Example

A rectangular table top is 3.5 m² in area. If the table is 2m long, how wide is it?

Solution

Area of a rectangle is Length x Width. So, 3.5 = 2 x Width Width = 3.5 ÷ 2 = 1.75m