Question

Three circles of radii 7.9, 10.1, and 11.5 cm are mutually tangent. Find the area bounded by the three circles.

Answer 1

Bound area = area of triangle ABC - area of 3 circle sectors
Area of triangle: Use Heron's formula
Area of a circle sector = (sector angle/ 2 pi)* area of circle
e.g sector angle for circle with radius 7.9 is angle at A.
Use cosine formula to find sector angles A,B and C.
Hope this helps