OpenStax, Algebra and Trigonometry 2e §10.2 Non-right Triangles: Law of Cosines · Example 1 · Trigonometry · Laws of sines & cosines

Solving for an Angle of a SSS Triangle

Find the angle $α$ for the given triangle if side $a = 20,$ side $b = 25,$ and side $c = 18.$

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OpenStax, Algebra and Trigonometry 2e · §10.2 Non-right Triangles: Law of Cosines · Example 1

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