Based on the calculations, an approximate length AC of the marsh is equal to 513.0 meters.
In Mathematics and Euclidean Geometry, the law of cosine can be represented by the following mathematical equation;

Where:
A, B, and C represent the side lengths of a triangle.
In order to determine an approximate length AC of the marsh, we would have to apply the law of cosine as follows:

AC = 513.0214 ≈ 513.0 meters.
Complete Question:
To approximate the length of a marsh, a surveyor walks x = 410 meters from point A to point B, then turns 75 degrees and walks 220 meters to point C (see figure). Approximate the length AC of the marsh. (Round your answer to one decimal place. )