There is an equilateral triangle inside a circle. the radius of the circle is 21. How do i find the length of the side of the triangle?
The side length will be given by :
s = √[ 2*21^2 - 2(21)(21)cos(120) ] =
√[2*21^2 - 2(21)(21)(-1/2)] =
√[2*21^2 + (21)(21)] =
√[3*21^2] =
21 √ 3 = about 36.37 units
