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In the Below Fig. D and E Are Two Points on Bc Such that Bd = De = Ec. Show that Ar (δAbd) = Ar (δAde) = Ar (δAec).

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Question

In the below fig. D and E are two points on BC such that BD = DE = EC. Show that ar
(ΔABD) = ar (ΔADE) = ar (ΔAEC).

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Solution

Draw a line through A parallel to BC

Given that, BD= DE = EC
We observe that the triangles ABD and AEC are on the equal bases and between the same
parallels C and BC. Therefore, Their areas are equal.
Hence, ar ( ABD) = ar (ΔADE) = ar ( ΔACDE)

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Chapter 14: Areas of Parallelograms and Triangles - Exercise 14.3 [Page 46]

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R.D. Sharma Mathematics [English] Class 9
Chapter 14 Areas of Parallelograms and Triangles
Exercise 14.3 | Q 15 | Page 46

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