# Substitute the exact values to find a missing length

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

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

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The next lesson in Trigonometry 3 is "Use trigonometry to solve bearing problems"