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D and E are points on sides AB and AC respectively of ΔABC such that ar (DBC) = ar (EBC). Prove that DE || BC. - Mathematics

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Question

D and E are points on sides AB and AC respectively of ΔABC such that

ar (DBC) = ar (EBC). Prove that DE || BC.

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Solution

Since ΔBCE and ΔBCD are lying on a common base BC and also have equal areas, ΔBCE and ΔBCD will lie between the same parallel lines.

∴ DE || BC

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Chapter 9: Areas of Parallelograms and Triangles - Exercise 9.3 [Page 163]

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NCERT Mathematics [English] Class 9
Chapter 9 Areas of Parallelograms and Triangles
Exercise 9.3 | Q 7 | Page 163

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