### Home > INT3 > Chapter 7 > Lesson 7.2.3 > Problem 7-81

7-81.

Eugene wants to use the cosine ratio to calculate *y*in this triangle. Homework Help ✎Which angle should he use to write an equation and solve for

*y*using the cosine ratio? Why?Write an equation and solve for

*y*using cosine.

He'll need the adjacent side and the hypotenuse. To which angle is *y* adjacent?