Q118 of 131 Page 226

A design is made up of four congruent right triangles as shown in Fig. 9.63. Find the area of the shaded portion.

Area of one triangle = × 10 × 30 = 150 cm2


Area of 4 such triangles = 4 × 150 = 600 cm2


Since the triangles are congruent, it can be concluded that the side of the square = 10 + 30 = 40 cm


Area of square = 402 = 1600 cm2


Area of shaded portion = 1600 – 600 = 1000 cm2


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