(Jon of the Clue Crew shows a line segment sweeping out a circle on the monitor.)  Euclid's third postulate tells us that from any line segment, a circle can be drawn with one endpoint as the center & the segment itself as this line
If two 
lines are drawn which intersect a third in such a way that the sum of the inner ... 
Euclid's fifth postulate cannot be proven as a theorem, although this was 
attempted by... [DOC] [TLE] Euclid's Postulates: Geometry and Mathematics Explained [PAR] Jul 4, 2012 ... Euclid's first postulate states that any two points can be joined by a straight line 
segment.