calculate distance and bearing from Unistis to Dinocilos

Question

two ships set sail from the port of Elrocious. one sail to Unistis a distance of 500km on a bearing of 215 degrees. the other ship sails to Dinocilos on a bearing of 15 degrees and a distance of 400km

Answer 1

use cosine law (draw a picture to visualize)

A= sqrt(b^2 + c^2 + 2bc(cos200))  use 200 as degree as it's the difference between the two

A = sqrt(400^2 + 500^2 + 2(400)(500)(cos200))

A = sqrt(160000+250000+194875)

A = 777.74 km