Question

    In triangle ABC, if the sides are a = 13 cm, b = 14 cm,

    and c = 15 cm, find the circumradius (R).
    A 8.125 cm Correct Answer Incorrect Answer
    B 6.125 cm Correct Answer Incorrect Answer
    C 8.75 cm Correct Answer Incorrect Answer
    D 9 cm Correct Answer Incorrect Answer

    Solution

    Using the formula: R = (abc) / (4 × Area). Area using Heron’s formula: s = (13 + 14 + 15) / 2 = 21 cm, Area = √(21 × (21 - 13) × (21 - 14) × (21 - 15)) = √(21 × 8 × 7 × 6) = 84 cm². Thus, R = (13 × 14 × 15) / (4 × 84) = 8.125 cm.

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