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Topic: What does one call vector geometry without a coordinate system?
Replies: 32   Last Post: Sep 9, 2013 4:45 PM

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 FredJeffries@gmail.com Posts: 1,845 Registered: 11/29/07
Re: What does one call vector geometry without a coordinate system?
Posted: Aug 30, 2013 8:29 PM

On Friday, August 30, 2013 4:30:23 PM UTC-7, lite.o...@gmail.com wrote:
> I remember in grade school (grade 8 or 9ish) we did geometry with vectors as a tool but without any coordinate system.
>
> We often picked a random point and called it O, then proved things like if M was midpoint between two points A, B, then:
>
> OM = 1/2 * (OA + OB)
>
> A lot of stuff was proven with just points and vectors from points to other points (with the fact OX = -XO used heavily).
>
> What's the name of this geometry? I'm thinking of looking this stuff up again.

Affine Geometry
http://persweb.wabash.edu/facstaff/footer/courses/M225/Handouts/Affine.pdf