# A triangle has sides A, B, and C. Sides A and B are of lengths 5 and 11, respectively, and the angle between A and B is (11pi)/12 . What is the length of side C?

Apr 15, 2016

$C \approx 15.88$

#### Explanation:

Law of Cosines:

$c = \sqrt{{a}^{2} + {b}^{2} - 2 a b \cos C}$

c=sqrt(5^2+11^2-2xx5xx11xxcos((11pi)/12)

c=sqrt(25+121-110cos ((11pi)/12)

$c \approx 15.88$