Q26 of 83 Page 356

In the given figure, ABCD is a rectangle inscribed in a quadrant of a circle of radius 10cm. If AD = 25cm, then area of the rectangle is

Given: ABCD is a rectangle inscribed in a quadrant of a circle of radius 10cm and AD = 25cm


Consider Δ ADC


By Pythagoras theorem


AC2 = AD2 + DC2


102 = (25)2 + AC2


AC2 = 102—(25)2


AC2 = 100 – 20 = 80


AC = 45


Area of rectangle = length × breadth = DC × AD


Area of rectangle = 45 × 25 = 40cm2


∴ Area of rectangle = 40cm2

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Look at the statements given below:

(I) A parallelogram and a rectangle on the same base and between the same parallels are equal in area.


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The question consists of two statements, namely, Assertion (A) and Reason (R). Choose the correct answer.











Assertion (A)



Reason (R)



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Then, ar(∆AOD) = ar(∆BOC)




Triangles on the same base and between the same parallels are equal in areas.