Law of Sines

This applet will help you to explore the law of sines. Play around with the triangle, dragging the points around and observe what happens to the lengths of the sides of the triangle, as well as the sines of the angles of the triangle. Then answer the questions below.

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Questions to Consider:

1. Because we're not dealing exclusively with right triangles, why does it make sense to look at the sines of angles A, B, and C?

2. Do you notice any correlation between the sines of A, B, and C, and the lengths of a, b, and c?

Click on the box to show the ratio of the sines of the angles to their opposite sides.

3. What do you notice?

4. What happens when you move the verticies of the triangle around? Do these ratios change? Stay the same?

5. What conclusions do you make from this exercise?

6. How would your conclusion be helpful to us in the future?

Morgan Summers, Created with GeoGebra