# Finding the perimeter of a rectilinear shape

## Home learning focus

Learn how to find the perimeter of a rectilinear shape.

This lesson includes:

• one video
• three interactive activities

# Learn

What is the perimeter?

This shape looks much more complicated than a rectangle, but the method of working out the perimeter is exactly the same.

Add together the lengths of all the sides to find it.

2 + 2 + 3 + 3 + 5 + 5 = 20

The perimeter is 20 cm

### Finding the unknown sides

Watch the video below from BBC Bitesize on finding the perimeter of a rectilinear shape when you don't know the length of every side.

A rectilinear shape is a shape that has straight sides and right angles.

# Practise

## Activity 1

Perimeter worksheet

Try this worksheet from Classroom Secrets Kids. Print it out or write your answers on paper.

## Activity 2

Make a shape

Cut out 12 squares of paper of equal size or use 12 square sticky notes (you may have these from yesterday's activity). Arrange them into a rectilinear shape.

What is the perimeter of this shape?

Now rearrange the pieces of paper into a new shape. How many different shapes can you make and find the perimeter of?

## Activity 3

Rectilinear shapes

Try the worksheet below from Pearson Power Maths.Print it out or write the answers on paper.

All done? Check the answers here

# There's more to learn

Have a look at these other resources around the BBC and the web.