# Substitute the exact values to find a missing length

In this lesson, we will find a missing length of a right angled triangle using prior knowledge of exact trigonometry ratios for 0°, 30°,45°,60° and 90°

# Video

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# Worksheet

These slides will take you through some tasks for the lesson. If you need to re-play the video, click the ‘Resume Video’ icon. If you are asked to add answers to the slides, first download or print out the worksheet. Once you have finished all the tasks, click ‘Next’ below.

# Lesson summary: Substitute the exact values to find a missing length

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## Time to move!

Did you know that exercise helps your concentration and ability to learn?

For 5 mins...

Move around:

Jog

On the spot:

Dance