Question

3.AD is an altitude of  ABC in which AB=AC .show that AD bisects BC and A

Answer 1

Answer:

▣ Diagram :

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▣ Given:

AD is an altitude of an isosceles triangle.

Therefore, AB = BC

▣ To Prove:

i) AD Bisects BC

ii) AD bisects ∠A

▣ Proof :

i) In ∆ADB and In ∆ADC

➝ AB = AC ......[Given]

➝ AD = AD ......[Common]

ஃ ∆ADB ≅ ∆ADC .......[RHS rule]

ஃ BD = CD .......[CPCT]

________________....

ii) $\because\:$ ∆ADB ≅ ∆ADC

⛬ ∠BAD = ∠CAD .......[CPCT]

⛬ AD bisects ∠A