Illuminations: Law of Sines and Law of Cosines

Law of Sines and Law of Cosines
In this unit, students learn the Law of Sines and the Law of Cosines and determine when each can be used to find a side length or angle of a triangle.

Individual Lessons

Lesson 1 - Law of Sines

In this lesson, students will use right triangle trigonometry to develop the law of sines.

Lesson 2 - Law of Cosines

In this lesson, students use right triangle trigonometry and the Pythagorean theorem to develop the law of cosines.

NCTM Resources

Principles and Standards for School Mathematics
National Council of Teachers of Mathematics Thinkfinity
More and Better Mathematics for All Students
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