Brahmagupta's formula
From Wacklepedia - The Free Encyclopedia
In
geometry,
Brahmagupta's formula gives the
area of a
cyclic quadrilateral whose sides have lengths
a,
b,
c,
d as:
-
where s=(a+b+c+d)/2.
Heron's formula for the area of a triangle is the special case obtained by taking d=0.