# A triangle has sides A, B, and C. Sides A and B are of lengths 5 and 1, respectively, and the angle between A and B is (11pi)/12 . What is the length of side C?

Oct 6, 2016

#### Answer:

Length of side C is $5.97 \left(2 \mathrm{dp}\right) u n i t$

#### Explanation:

The sides A,B and their included angle are A=5;B=1; /_c=11*180/12=165^0
Applying cosine law , ${C}^{2} = {A}^{2} + {b}^{2} - 2 \cdot A \cdot B \cdot \cos c$ we get $C = \sqrt{{5}^{2} + {1}^{2} - 2 \cdot 5 \cdot 1 \cdot \cos 165} = \sqrt{35.66} = 5.97 \left(2 \mathrm{dp}\right) u n i t$[Ans]