sorry to say!!!
you don't know how to teach???? bera ghark karhy hain sub ka :(
don't assume that everybody knows everything.. you are escaping lot of things in middle and saying always that convince yourself.... the students get stuck and feel angers.
It would be more better i you solve some examples on whiteboard manually and explain at least one example.
Its look like a battlefield where someone riding a galloping horse and trying to escape the enemy behind him...
need some teaching scales and power how to transfer the knowledge to the students.... MATH is not an easy subject.
Virtual Uni.. plz hire some experienced tutors to avoid bad reputations.