Question

if triangle ABC is an isosceles triangle such that ab=ac,then prove that altitude ad from a on bc bisects bc

Answer 1

Dear Student,

In $△$ADB and $△$ADC
$\angle$ADB = $\angle$ADC = 90 (Since AD is an altitude)
AD = AD (Common Side)
AB = AC (Isosceles Triangle)

Therefore, the two triangles are congruent by RHS test
Hence, BD = DC

therefore, D bisects BC

Regards