• Choice D

    The Law of Cosines (also called the Cosine Rule) :

    c2=a2+b22abcosC=802+12022×80×120cos127°=180c^2=a^2+b^2-2ab\cos C=80^2+120^2-2\times 80 \times 120 \cos 127°=180

    Skills you are tested for:

    Was this explanation helpful?
  • Comments

    To leave a comment,