# Classifying quadrilaterals

## Learning focus

Learn about the different types of quadrilaterals and their properties.

This includes:

- a quiz
- a learning summary
- one video
- one activity

# Quiz

To get started, let's see how well you know this topic already. Take the quiz below to find out.

# Learn

You can classify shapes based on their properties.

**Properties** are qualities that a shape has. Examples of shape properties are:

- number of sides
- length of sides
- number of angles (corners)
- types of angle (acute, obtuse, right-angle)
- perpendicular and parallel lines

Watch the video below from KS2 Maths which is all about **polygons.** Polygons are 2D shapes with 3 or more straight sides.

All quadrilaterals are polygons, but there are other types of polygons too.

## Quadrilaterals

Quadrilaterals have **4 straight sides** and **4 angles**. These are the common properties.

Here are some examples of quadrilaterals and their properties:

## Square

Properties:

- all sides all of an equal length
- angles that are all right-angles (perpendicular lines)
- 2 pairs of parallel lines

## Rectangle

Properties:

- 2 sides longer than the others
- angles that are all right-angles
- 2 pairs of parallel lines

## Trapezium

Not all trapeziums look the same. This trapezium has:

Properties:

- 1 pair of parallel lines (all trapeziums have this)
- 2 sets of equal angles
- 2 lines equal length and 2 that aren’t
- 2 obtuse angles and 2 acute

## Parallelogram

Properties:

- 2 pairs of parallel lines
- 2 acute and 2 obtuse angles
- 2 pairs of sides that are equal length

## Rhombus

Properties:

- all sides equal length
- 2 pairs of parallel lines
- opposite angles are equal

As you can see, some quadrilaterals share more properties than four sides and four angles.

Look at this rhombus and square.

These two quadrilaterals also share **2 pairs of parallel lines** and **4 equal lengths.**

You can classify and compare shapes by using a Venn diagram.

Each shape has been placed in the section of the Venn diagram it belongs in.

Because the square doesn’t have any acute angles or a pair of parallel sides that are longer in length, then it stays outside of the Venn diagram.

You could also use a Carroll diagram to classify these shapes.

The shapes have been placed in the sections where they share two of the properties from the Carroll diagram.

# Practise

## Activity 1

**Finding quadrilaterals**

Look around you. Can you see any quadrilaterals? Draw and label the types of quadrilaterals you can see.

Quadrilaterals have four sides. Can you draw a four-sided shape which is **not** a quadrilateral?

# Play

Play **Guardians: Defenders of Mathematica** to learn more and sharpen your skills on this topic.