Q4 of 99 Page 258

The lengths of three sides of our triangular park are 65 m, 70 m and 75 m. Let us write by calculating the length of perpendicular drawn from opposite vertex on the longest side.

Given,


In a triangular park length of three sides are AB = 65 m, AC = 70 m and BC = 75 m and AD = x m, is the height of the perpendicular drawn to BC


AD is the perpendicular drawn on the longest side BC


Since all the three sides are different of the triangular park it forms a scalene triangle




Area of a scalene triangle with given three sides


Where a, b, and c are the sides of the triangle


and s (semi perimeter of triangle )


Here,


⇒


⇒ s = 105 m


Area of triangular park m2


m2


= m2


= 2100 m2


But, Area of triangle


So area of triangle ABC


⇒


⇒


⇒ x = 56 m


Therefore, height of the perpendicular drawn from the vertex opposite to longest side is 56m


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