Question
The lengths of three medians in a triangles are 21 cm,
28 cm, 35 cm. What is the area of that traingle (in cm 2 )?Solution
Here s = (a+ b+ c )/2 = (21 + 28 + 35) /2 = 84/2 = 42 cm If a, b & c are medians of any triangle , then area of the triangle = 4/3 √(s(s - a)(s - b)(s - c)) = 4/3 √(42(42 - 21)(42 - 28)(42 - 35)) = 4/3 √(42 × 21 × 14 × 7) = (4/3) × 294 = 392 cm²
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