Q85 of 131 Page 226

In the given triangles of Fig. 9.39, perimeter of ∆ABC = perimeter of ∆PQR. Find the area of ∆ABC.

Given, perimeter of ∆ABC = perimeter of ∆PQR


AB + BC + CA = PQ + QR + RP


AB + 5 + 13 = 6 + 10 + 14


AB + 18 = 30


∴ AB = 30 – 18 = 12 cm


We know that, Area of triangle = × b × h


∴ Area of ∆ABC = × BC × AB = × 5 × 12 = 30 cm2


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