Question
Find the area of triangle having sides 7m, 8m, and
9m.Solution
 Here s = semi perimeter = (7 + 8 + 9)/2 =12m So area of this triangle = √(12(12 - 7)(12 - 8)(12 - 9))  = √(12 × 5 × 4 × 3) = 12√5 m 2 
- 2, 2, 6, 30, ?, 1890 
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