A triangle has sides A, B, and C. If the angle between sides A and B is (3pi)/8, the angle between sides B and C is (7pi)/12, and the length of B is 3, what is the area of the triangle?

1 Answer
Mar 25, 2016

Area ~~ 30.766" units"^2" "to 3 dp

Explanation:

Tony B

Sum of internal angles for a triangle is 180^o-> pi" radians"

So /_AC= 1/24 pi ->7 1/2color(white)(.)^o

h=Bsin(/_AB) = 3 sin(3/8 pi) ~~2.7716

" "A/sin(/_BC)=B/sin(/_AC)

=> A = (Bsin(/_BC))/sin(/_AC)~~22.201

'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Area = A/2xxh

Area = (Bsin(/_BC))/(2sin(/_AC))xxBsin(/_AB)

Area = (3sin(/_BC))/(2sin(/_AC))xx3sin(/_AB) ~~ 30.766" "to 3 dp