2012 · Q92
The area of a circle inscribed in an equilateral triangle is 154 cm^2. What is the perimeter of the triangle?
Elementary MathematicsMensuration
- A21 cm
- B42*sqrt(3) cm
- C21*sqrt(3) cm
- D42 cm
Explanation
pi*r^2 = 154 gives r = 7; side = 6r/sqrt(3) = 14*sqrt(3), perimeter 42*sqrt(3) cm.