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The Law of Cosines

Unknown Grade45 min

Learning Objective

I can apply the law of cosines to find the lengths of the sides of a triangle when given two sides and the included angle.

Lesson Flow

Watch Video

5 min

Law of cosines | Trig identities and examples | Trigonometry | Khan Academy

Unknown Channel

Exit Ticket

5 min

“Reflect on what you learned today.”

Teacher Guide

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  • Answer keys for all questions
  • Differentiation strategies
  • Extension activities
  • Printable student handouts

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