A triangle has sides A, B, and C. The angle between sides A and B is (pi)/2π2. If side C has a length of 18 18 and the angle between sides B and C is pi/12π12, what is the length of side A?

1 Answer
Nov 17, 2017

Length of side AA is 4.66(2dp)4.66(2dp) unit.

Explanation:

Angle between Sides A and BAandB is /_c= pi/2=180/2=90^0c=π2=1802=900

Angle between Sides B and CBandC is /_a= pi/12=180/12=15^0 :.

Angle between Sides C and A is /_b= 180-(90+15)=75^0

The sine rule states if A, B and C are the lengths of the sides

and opposite angles are a, b and c in a triangle, then:

A/sina = B/sinb=C/sinc ; C=18 :. A/sina=C/sinc or

A/sin15=18/sin90 :. A = 18* sin15/sin90 ~~ 4.66(2dp)unit

Length of side A is 4.66(2dp)unit. [Ans]