Question

AD is the bisector of angle A of triangle ABC in which AB =AC prove that AD is perpendicular to BC.
(please ans fast)
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Answer 1

Step-by-step explanation:

as AD is median for isosceles triangle ABC AD is perpendicular to BC

Answer 2

Answer:

Step-by-step explanation:

Given

ABC is a triangle and AD is a bisector of angle A.

Angle BAD=angle DAC

AB=AC

To prove

AD is perpendicular to BC

ie, Angle ADC=90°

Proof

In∆ABC,

AB=AC

Angle ABC=angle ACB

By angle sum property of triangle,

angle BAC+ABC+BCA=180°

BAC+2ACB=180°

BAC=180-2ACB

ANGLE DAC=180-2ACB/2

=90-ACB........(1)

In ∆ADC,

DAC+ACD+ADC=180°

90-ACD+ACD+ADC=180°

ADC=90°

Hence proved