What is HERON'S formula? with example and explanation.

**Heron's formula** is used to find the area of a triangle in terms of the length of its sides. This formula is applicable to all types of triangles.

Let *a, b* and *c* denotes the length of the sides of ∆ABC.

Area of , where *s* is the semi - perimeter of the triangle.

∴ semi - perimeter of .

Take an example of a ∆ ABC where sides are given as 250 cm, 170 cm and 120 cm and we have to find out the area of ∆ABC.

Area of triangle, , where

∴ Area of triangle,

Hence, area of triangle is 9000 cm^{2}.

**
**