Item 1

If the circle with centre O has area 9𝜋, What is the area of the equilateral triangle ABC?

  • Solution

    Given the area of the circle is 9𝜋

    Then, the radius of the circle will be 3

    Therefore, AD=6  (diameter of the circle.)

    AD is the height of an equilateral triangle.

    12×a ×6 = 34×a2

    a =123

    The area of the equilateral triangle