Find the area of an equilateral triangle (not 1/2bh) with sides of... say... 6?
semiperimeter s=18/2=9
area=sqrt(s*(s-a)(s-b)(s-c)
but a=b=c=6
so area= sqrt (9(3^3))=sqrt(9*9*3)
= 9sqrt3
area=sqrt(s*(s-a)(s-b)(s-c)
but a=b=c=6
so area= sqrt (9(3^3))=sqrt(9*9*3)
= 9sqrt3