Question 319662
Points A,B and C lie on a circle and form an equilateral triangle.
 If AB = 12 what is the circumference of the circle.
:
Draw this out.
The centroid of the equilateral triangle is also the center of circle.
The hypotenuse of the triangle formed by drawing the medians through the
 center is also the radius (r).
:
Cos(30) = {{{6/r}}}
.866r = 6
r = {{{6/.866}}}
r = 6.93
Find the circumference
C = {{{2*pi*6.93}}}
C = 43.53