Hello,
I've just checked out the video section and there is one there, under miscellaneous 'checking for square' - posted by Steve Maskery, which is good. The theorem behind it is 'Thales Theorem'. Check it out in Wikipedia. Good old Mr Truscott (my old maths teacher) strikes again! Only reason I'm any good at maths is that Mr Truscott used to tell us stories of his experiences as a bomber pilot in WW2 but only if we finished the work first.
I've just checked out the video section and there is one there, under miscellaneous 'checking for square' - posted by Steve Maskery, which is good. The theorem behind it is 'Thales Theorem'. Check it out in Wikipedia. Good old Mr Truscott (my old maths teacher) strikes again! Only reason I'm any good at maths is that Mr Truscott used to tell us stories of his experiences as a bomber pilot in WW2 but only if we finished the work first.