to approximate the length of a marsh a surveyor walks 250 me

to approximate the length of a marsh, a surveyor walks 250 meters from point A to point B , then turns 75 degrees and walks 220 meters to point C. Approximate the length AC of the marsh.

Solution

We have to use law of cosine here

AC²=AB²+BC²-2 AB BC cos B

AC²= 250²+220²-2 (250)(220)cos 75

AC²= 110900- 110000cos 75

AC=287 m