
geometry problem
hey,
Help is needed with the following geometry problem:
Consider a triangle ABC. Insert a point D on the side Ac and a point E on the side AB. Draw a line through DE. The intersection between the line through DE and the line through BC is called F.
Drawing an arbitrary triangle as mentioned above we can compute the following:
AD*CF*BE
BF*AE*CD
It is possible to draw the triangle in a program called geogebra. By doing this we can move the points D and E and observe the change.
The question is the following: formulate an expression which apparently holds true for the abovementioned triangle.
Thanks a bunch.

Re: geometry problem
I think you are referring to Menelaus' theorem, in that case, the ratio AD*CF*BE to BF*AE*CD is 1, i.e. they're equal.

Re: geometry problem
Thank you very much. Just one more question. I looked up the theorem on the Internet and sometimes I came across the ratio as being 1. why the differene?

Re: geometry problem
Some texts say 1 or 1, it's 1 if you treat them as vectors (e.g. AD = DA). But if you're concerned only with magnitudes (e.g. AD), it's 1.