maths (circle)

The (circumscribed) circle passing through the three vertices of any triangle with sides a,b,c and area K is given by
R=abc/4K=15*15*6/(4*sqrt(1944)=25*sqrt(6)/8=7.6546...

To find the area:
if a,b, c are the sides of a triangle, and s=(a+b+c)/2,
The area of an inscribed circle is given by
K=sqrt(s(s-a)(s-b)(s-c))
For a=15,b=15,c=6, s=(15+15+6)/2=18
K=sqrt(18*3*3*12)=sqrt(1944)

Alternatively, we can calculate from the traditional formula
K=base*height/2=6*6*sqrt(6)=sqrt(1944)