Question

    The area of the circumcircle of an equilateral triangle

    is 3π cm². The perimeter of the triangle is:
    A 5 cm Correct Answer Incorrect Answer
    B 9 cm Correct Answer Incorrect Answer
    C 8 cm Correct Answer Incorrect Answer
    D 6 cm Correct Answer Incorrect Answer
    E None of these Correct Answer Incorrect Answer

    Solution

    Let side of an equilateral triangle = a cm ∴  circumcircle radius = a/√3 cm ∴  area of circumcircle = π(a/ √3)2 => πa2/3 = 3π ⇒  a2 = 9 ⇒  ∴ a  = 3 cm ∴  Perimeter = 3 × a = 9 cm

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