हिंदी

In ∆ABC, AB = AC. Show that the altitude AD is median also.

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प्रश्न

In ∆ABC, AB = AC. Show that the altitude AD is median also.

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उत्तर

In ∆ABD and ∆ADC,

AB = AC                     ...(Since is an isosceles triangle)

AD = AD                     ...(common side)

∠ADB = ∠ADC            ...(Since AD is the altitude so each is 90°)

⇒ ΔADB ≅ ΔADC           ...(RHS congruence criterion) 

BD = DC               ...(cpct)

⇒ AD is the median.

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Criteria for Congruence of Triangles
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 9: Triangles [Congruency in Triangles] - Exercise 9 (A) [पृष्ठ १२२]

APPEARS IN

सेलिना Concise Mathematics [English] Class 9 ICSE
अध्याय 9 Triangles [Congruency in Triangles]
Exercise 9 (A) | Q 12 | पृष्ठ १२२

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