What is the distance between deer A and deer C?

Three deer, A, B, and C, are grazing in a field. Deer B located 64 m from dear A at an angle of 54� north of west. Deer C is located 74� north of east relative to dear A. The distance between deer B and C is 92 m. What is the distance between deer A and C? (Hint: Consider the law of cosines given)