Prove the perpendicular bisector of chord passes through the centre of the circle 
Hello, can someone please give me a simple proof to the following theorem:
"The perpendicular bisector a chord passes through the centre of the circle."
I have attached a diagram of what I mean and web link of a proof that I did not understand below.
https://proofwiki.org/wiki/Perpendicular_Bisector_of_Chord_Passes_Through_Center
Please explain simply and fully because I have an exam on this tomorrow. Also, could you explain the converse theorem whereby a bisector passes through the centre of the circle, prove it's perpendicular and a perpendicular line passes through the centre, prove it bisects the chord.

The proof in the picture is the simplest possible one. All you have to do is write the conditions for congruence thus proving that the triangles in the above picture are congruent. This is the best possible approach to the given question.
