हिंदी

D, E and F Are the Mid-points of the Sides Ab, Bc and Ca of an Isosceles δAbc in Which Ab = Bc. Prove that δDef is Also Isosceles.

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प्रश्न

D, E and F are the mid-points of the sides AB, BC and CA of an isosceles ΔABC in which AB = BC. Prove that ΔDEF is also isosceles.

योग
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उत्तर


E and F are mid-points of BC and AC

Therefore, EF = `(1)/(2)"AB"`......(i)

D and F are mid-points of AB and AC

Therefore, DF = `(1)/(2)"BC"`......(ii)
But AB = BC
From (i) and (ii)
EF = DF
Therefore, ΔDEF is an isosceles triangle.

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अध्याय 11: Midpoint and Intercept Theorems - Exercise 15.1

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फ्रैंक Mathematics Part 1 [English] Class 9 ICSE
अध्याय 11 Midpoint and Intercept Theorems
Exercise 15.1 | Q 7

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