What radius of a circle is required to inscribe an equilateral triangle with an area of 270.633 cm2 and an altitude of 21.65 cm?

1. 
All three angles are equal and their sum is 180. 
3 (3x-12) = 180 
9x -36 = 180 
9x = 180+36 
9x = 216 
x = 216/ 9 = 24 

2. 
Area of an equilateral triangle = (sqrt(3)/4 ) s^2 = 270.633 
s^2 = 270.633 / [ sqrt(3) /4] 
s^2 = (4)(270.633) / sqrt(3) 
s^2 = 625 
s = 25 (side) 

Follow the procedure in the link: we don't need the altitude. 
r = 25/sqrt(3) =14.43 

Yes i also think it is b