Let circle inscribed in equilateral triangle
Be with centre O and radius ‘r’
Area of circle = πr2
But given that area = 154 cm2.
πr2 = 154
22/7xr2=154
r2=7×7
r = 7cms
Radius of circle = 7cms
From fig. at point M, BC side is tangent at point M, BM ⊥ OM. In equilateral triangle, the perpendicular from vertex divides the side into two halves
ΔBMO is right triangle, by Pythagoras theorem