The formula given by Heron about the area of a triangle, is also known as Heron’s formula. It is stated as:
Area of triangle = √s x (s-a) x (s-b) x (s-c)
where a, b and c are the sides of the triangle, and s = semi-perimeter, i.e., half the
perimeter of the triangle = (a + b + c)/2

Area of a quadrilateral whose sides and one diagonal are given, can be calculated by dividing the quadrilateral into two triangles and using the Heron’s formula.