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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. - Mathematics

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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

उत्तर

DF = `1/2`BC          ...(i)

DE = `1/2`AC        ...(ii)

EF = `1/2`AB       

EF = `1/2`BC        ...(iii)       ...[AB = BC]

From equation (i) & (ii)

DF = EF

Hence, DEF is also isosceles triangle. 

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  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 12: Mid-point and Its Converse [ Including Intercept Theorem] - Exercise 12 (A) [पृष्ठ १५०]

APPEARS IN

सेलिना Concise Mathematics [English] Class 9 ICSE
अध्याय 12 Mid-point and Its Converse [ Including Intercept Theorem]
Exercise 12 (A) | Q 3 | पृष्ठ १५०

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