A triangle has sides A, B, and C. The angle between sides A and B is pi/12 and the angle between sides B and C is pi/12. If side B has a length of 1, what is the area of the triangle?

1 Answer
Feb 17, 2018

Area of triangle Delta ABC = (1/2) a c sin B = color(blue)(0.134

Explanation:

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Given hatC = pi/12, hatA = pi/12, b = 1

It’s an isosceles triangle with sides a & c equal, as their angles are equal.

hatB = pi - pi / 12 - pi / 12 = (5pi)/6

a / sin A = b / sin B = c / sin C

a / sin ((pi)/12) = c / sin ((pi)/12) = 1/ sin ((5pi)/6)

a = c = (1 * sin (pi/12)) / sin ((5pi)/6) = 0.5176

Area of triangle Delta ABC = (1/2) a c sin B

=> (1/2) * 0.5176 * 0.5176 * sin ((5pi)/6) = color(blue)(0.134