is the point on the line such that . It can also be thought of as the point of intersection of two Parallel lines.

**References**

Behnke, H.; Bachmann, F.; Fladt, K.; and Suss, W. (Eds.). Ch. 7 in *Fundamentals of Mathematics, Vol. 3: Points at Infinity.*
Cambridge, MA: MIT Press, 1974.

© 1996-9

1999-05-25