Q92 of 131 Page 226

Find the area of a square inscribed in a circle whose radius is 7 cm (Fig. 9.45).

[Hint: Four right-angled triangles joined at right angles to form a square]



Given a square ABCD inscribed in a circle of radius 7 cm.


For ∆AOB, OA = OB = 7 cm


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


Area of ∆AOB = × OB × OA = × 7 × 7 = cm2


Since the square is made up of four congruent triangles, area of square ABCD = 4 × = 98 cm2


Area of the inscribed square = 98 cm2


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