### Home > A2C > Chapter 13 > Lesson 13.2.2 > Problem 13-120

13-120.

If the side lengths of *∆ABC* are *a* = 9, *b* = 10, and *c* = 5, calculate the measure of the largest angle. Homework Help ✎

The largest angle is opposite the longest side.

*m*∠ B ≈ 86.17°