Hjelmslev's Theorem
When all the points 
on one line are related by an Isometry to all points 
on another, the Midpoints of thesegments 
are either distinct and collinear or coincident.
- Polygonal Spiral
- Polygon Circumscribing Constant
- Polygon Construction
- Polygon Division Problem
- Polygon Fractal
- Polygon Inscribing Constant
- Polygon Triangulation
- Polygram
- Polyhedral Formula
- Polyhedral Graph
- Polyhedron
- Polyhedron Coloring
- Polyhedron Compound
- Polyhedron Dissection
- Polyhedron Dual
- Polyhedron Hinging
- Polyhedron Packing
- Polyhex
- Polyiamond
- Polyking
- Polylogarithm
- Polymorph
- Polynomial
- Polynomial Bar Norm
- Polynomial Bracket Norm