Question

What is the reason for statement 3 in this proof?

Answer 1

Answer:

A. Definition of angle bisector

Step-by-step explanation:

Given that ΔABC is an isosceles triangle where AB = BC, and that BD bisects ∠ABC, then by the definition of angle bisection of ∠ABC, we have;

m∠ABD = m∠CBD

The correct option is option A. Definition of angle bisector

Also, given that ΔABC is an isosceles triangle and BD is the angle bisector of ∠ABC, we get;

AD = CD and BD = BD

We can therefore, also find that ΔABD ≅ ΔCBD by Side Side Side (SSS) rule of congruency