In this activity, we will be looking at similar shapes.

Similar shapes have matching corresponding angles and corresponding sides which are in the same **ratio**.

In these two triangles, the angles match.

The first triangle has sides which are double the length of the sides of the second triangle.

The ratio of the bases is 4 : 2 which simplifies like a fraction to 2 : 1

The ratio of the heights is 8 : 4, which simplifies like a fraction to 2 : 1

Let's look at a typical question!

__Example__

The rectangles below are similar.

Find the missing length.

**Answer**

The ratio of the bases is 1:3

This means the sides of the large rectangle are 3 times longer than the small rectangle (1 : 3)

To find the missing side we know it is 3 times longer than its corresponding side (3)

The missing side = 3 x 3 =** 9**

Let's have a go at the questions now.