Lesson 5

Discover

 

In Lesson 4 you learned that the sine law can be used for any triangle, including oblique and right triangles. Although it is true that the sine law can be applied to any triangle, sometimes you are not given all of the information you need to use the sine law.

 

Consider Jennifer and David’s problem. They have not been given enough information to conclude that their triangle is a right triangle, so they know that they can’t use the primary trigonometric ratios or the Pythagorean theorem. In math class, they learned that the sine law can be used for any triangle. However, they are not sure that they have enough information to use the sine law.

 

Share 1

 

Consider the triangle that David and Jennifer created to help them find the length of the rope they need to purchase.

 

 

With a partner, write the three equations for the sine law you learned in Lesson 4. Why can’t the sine law be used to find the length of

 

If required, save a copy of your discussion in your course folder.