Answer:
See Below.
Explanation:
We are given that ABC is a triangle in which AB = AC.
A circle passing through B and C also intersects the sides AB and AC at points D and E respectively.
And we want to prove that AD = AE.
By the secant-secant theorem (shown below), we know that:
We are given that AB = AC. So, by substitution:
And by dividing both sides by AB (AB ≠ 0), we acquire:
Q.E.D.