Algebra-2

Question Analysis
This problem assesses the application of the cosine function in a real-world context.

Key Concept Explanation
The cosine of an angle in a right triangle is the ratio of the length of the adjacent side to the length of the hypotenuse. Here, the ladder forms the hypotenuse, and the distance from the base of the ladder to the wall is the adjacent side.

Step-by-step Solution
1. Use the cosine of 60 degrees:
2. Set up the equation: