A triangle has sides A, B, and C. The angle between sides A and B is (pi)/4. If side C has a length of 18 and the angle between sides B and C is ( 3 pi)/8, what are the lengths of sides A and B?

1 Answer
Sep 26, 2017

Lengths of sides A and B are 23.52 unit each.

Explanation:

The angle between sides A and B is /_c =pi/4 = 180/4=45^0

Angle between sides B and C is /_a =(3pi)/8=(3*180)/8=67.5^0

Angle between sides C and A is

/_b=180-(45+67.5)= 67.5^0 : C =18 We know by sine rule

A/sina=B/sinb=C/sinc :. A= C* sina/sinc =18 * sin67.5/sin 45

:.A ~~ 23.52(2dp) , similarly B= C* sinb/sinc =18 * sin67.5/sin 45

:.B ~~ 23.52 (2dp). Lengths of A and B are 23.52 unit each. [Ans]