A triangle has sides A, B, and C. The angle between sides A and B is pi/6 and the angle between sides B and C is pi/12. If side B has a length of 2, what is the area of the triangle?
1 Answer
Mar 3, 2016
≈ 0.366 square units
Explanation:
I recommend you make a sketch.
Area can be calculated using either of the following formulae.
area
= 1/2ABsin(pi/6) " or " 1/2BCsin(pi/12) depending on which is used A or C will be required.
choose side A : Require use of
color(blue)" sine rule " The angle between A and C will also be required before progressing.
angle between A and C
= pi - (pi/6 + pi/12 ) = (3pi)/4 sine rule :
A/(sin(pi/12)) = B/(sin((3pi)/4))
rArr A = (2sin(pi/12))/(sin(3pi)/4) ≈ 0.732
rArr" area " = 1/2ABsin(pi/6) ≈ 0.366 " square units "