In triangle ABC angle bisectors AD, BE, and CF meet at I. If DI = 3, BD = 4, and BI = 5, then compute the area of triangle ABC.
Δ ABS is an isosceles triangle.
∠B = 2 [arctan(3 / 4)] = 73.73979529º
AD = tanB * BD = 13.71428571
Area = AD * BD = 54.85714286 u2
