# Recognise 2D and 3D shapes

## Learning focus

Learn how to recognise 2D and 3D shapes from descriptions of their properties.

This lesson includes:

• one catch-up quiz
• one learning summary

# Quiz

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

# Learn

2D shapes can be described by their sides, their angles and their symmetry.

• The sides might be equal in length and some might be parallel.

• The angles could be right angles, but sometimes they are greater than or less than a right angle.

• A 2D shape could have line symmetry or rotation symmetry, or both!

3D shapes are described by their faces, edges and vertices.

The faces can be the same shape or different, and a 3D shape could have a curved surface as well as flat faces.

## Example 1

Dawn describes a 2D shape as having 4 right angles. What shape could it be?

A square has 4 right angles and 4 equal sides.

A rectangle has 4 right angles, but not equal sides.

Dawn’s shape could be a square or a rectangle.

## Example 2

Bruce draws this quadrilateral. How can we describe it?

• It has 4 equal sides, and the opposite sides are parallel.
• It has 4 angles but none are right angles.
• The opposite angles are equal.

It is a rhombus.

## Example 3

Sophie draws this triangle. How can we describe it?

• It has 3 sides that are all different lengths.
• It has 1 right angle.

It is a right-angled scalene triangle.

## Example 4

Mika draws a shape with 5 equal sides and 5 equal angles. What is her shape?

A shape with 5 equal sides and 5 equal angles is a pentagon.

## Example 5

Chloe notices that her 3D shape has 5 flat faces. 4 of the faces are triangles.

She also counts that it has 8 edges and 5 vertices. What is her shape?

Chloe’s shape is a square-based pyramid.

# Play

Play Guardians: Defenders of Mathematica to learn more about this topic and test your skills.

# There's more to learn

Have a look at these other resources.