Question Analysis
The main focus is using trigonometric functions in right - triangle (where ) to find the length of side . Given and the length of the hypotenuse , we need to determine the length of the side adjacent to .
Key Concept Explanation
In a right - triangle, the cosine of an angle is defined as . Here, , the hypotenuse is , and the adjacent side is .
Step - by - Step Solution
1. Identify the relevant trigonometric function:
Since we know the hypotenuse and want to find the adjacent side to the given angle, we use the cosine function. The formula is .
2. Substitute the known values:
Given and