Hi absol,
I'm not sure about plane geometry in H3, but for O levels, this
is how I would teach my students. When they ask you to find the
length or angle of something, don't be boxed in by thinking how to
get that only, then find that you are stuck, and continue thinking
along that path. I have yet to refine my thoughts and tactics, but
the gist can boil down to two things so far:
1) Find out what angles/lengths are related to the answer you
are going to find (by whatever theorem). Then find those
angles/lengths, or if cannot, repeat the previous sentences. Then
slowly come back and find the answer.
In programming, this is called recursive functions :D It is
because of my programming background that I could understand H2
maths recurrence relations within minutes and start teaching
students.
2) Try a different theorem and repeat (1)
Also, if 3D was involved (as in physics or 3D vectors or 3D
trigo in earlier syllabus), then you can "cheat" by using your pens
in exams to make up the shape :D
So far, most of the questions can be solved by this general
algorithm. However, like you correctly mentioned, you will need
questions to practice.
