Question

please solve brainliest, expert and genius please solve this is anybody answers I will mark them as brainliest.

Answer 1

Given= angleA=36,AB=AC,and bisector of angleC meets AB at D.

To Prove=AD=BC.

Proof=angle B= angle C(angles opp. to equal sides are equal).
In ∆ABC,angle A +angle B+angle C=180(Angle sum property of a ∆).
36 + 2angle B=180(angle A = angle B).
2angle B=144
angle B=72.

angle C=72(angle B=angle C).
angleACD=angleBCD(bisector CD bisects angleC).
angle C=2*angleACD.
angleACD=angleC/2
angle ACD=36.


In ∆ ADC, angle A = angle ACD(36)
Hence sides AD=CD(sides opp. to equal angles are equal).


In ∆DBC,angle DCB + angle B + angle BDC= 180( angle sum property of ∆)
angle DCB= 180-36-72
angle DCB=72.
angle B = angle DCB
Hence sides DC=BC(sides opp. to equal angles are equal).
And sides AD =CD
So Sides BC=AD
HENCE PROVED.