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In ∆ABC, AB = 5 cm, BC = 8 cm and CA = 7 cm. If D and E are respectively the mid-points of AB and BC, determine the length of DE. - Mathematics

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Question

In ∆ABC, AB = 5 cm, BC = 8 cm and CA = 7 cm. If D and E are respectively the mid-points of AB and BC, determine the length of DE.

Sum

Solution

In ΔABC, we have AB = 5 cm, BC = 8 cm and CA = 7 cm.

Since, D and E are the mid-points of AB and BC, respectively.

By mid-point theorem, DE || AC

And DE = `1/2` AC = `7/2` = 3.5 cm

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Chapter 8: Quadrilaterals - Exercise 8.2 [Page 76]

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NCERT Exemplar Mathematics [English] Class 9
Chapter 8 Quadrilaterals
Exercise 8.2 | Q 8. | Page 76

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