Q6 of 50 Page 13

The perimeter of a triangle is 300 m. If its sides are in the ratio 3 : 5 : 7. Find the area of the triangle.

Sides of triangle are in ratio: 3 : 5 : 7



Since the perimeter of a triangle is given by:






Therefore sides of the triangle are:





When a, b and c are the sides of triangle and s is the semi-perimeter, then its area is given by:


A = where [Heron’s Formula]


= = 150


A =


A = = m2


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