Geometry

Question Analysis

We are given two sides (, ) and the included angle () in . The goal is to find the length of the third side , which can be achieved using the Law of Cosines.

 

Key Concept Explanation

The Law of Cosines formula is , where ,  are two sides of a triangle,  is the included angle between them, and  is the side opposite to angle . In , if we let , , and , we can use this formula to find .

 

Step - by - Step Solution

1. Substitute the values into the Law of Cosines formula:

, so .

, so