Question
Find the area of triangle having sides 8 m, 9 m, and 13
m.Solution
 Here s = semi perimeter = (8 + 9 + 13)/2 = 15 m So area of this triangle = √(15 (15 - 8)(15 - 9)(15 - 13))  = √(15 × 7 × 6 × 2) = 6√35 m 2 
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