Question

Use the Law of Cosines to find the missing angle.
Find m∠B, given a = 11, b = 12, and c = 17.

Answer 1

b^2=a^2+c^2-2ac*cosB

cosB=(a^2+c^2-b^2)/(2ac)

B=arcos[(a^2+c^2-b^2)/(2ac)]

B=44.664924531140738644131908835392

B≈44.7