2014 · Q42
AB and CD are two diameters of a circle of radius r and they are mutually perpendicular. What is the ratio of the area of the circle to the area of the triangle ACD?
Elementary MathematicsGeometry
- Aπ/2
- Bπ
- Cπ/4
- D2π
Explanation
Triangle ACD has base CD = 2r and height r, area r^2; circle area πr^2; ratio = π.