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Cosine Rule – Missing Side

Cosine Rule – Missing Side

How to use this applet:

  1. Click the "Generate Triangle" button to get a new triangle with two angles and one side.
  2. Determine the missing side using the Cosine Rule.
  3. Check your answer by toggling the "Show solution" checkbox.
1
Click the button to generate a random triangle
2
Apply the cosine rule

\( c^2 = a^2 + b^2 - 2ab\cos(C) \)

Side c = ? units