Re: [math-fun] Ambiguously placed cities

On 11/26/06, Andy Latto <Andy.Latto@gensym.com> wrote:

The fact that DMD' is perpendicular to CM shows that the distances CD and CD' are equal. But I don't see why AD and AD' should be equal in this contstruction.

They aren't --- by congruent triangles, AD' = BD and AD = BD'. I now see the point of the original problem --- permuting the distances still produces a viable distance chart. So what the problem statement must _avoid_ specifying is the assignment of distances to specific edges! WFL