Assertion: geometry's point | /r/CapableOf | lie on one line
Facets:
Source sentences:
text: Two figures in a plane are perspective from a point O if the lines joining corresponding points of the figures all meet at O. Dually, the figures are said to be perspective from a line if the points of intersection of corresponding lines all lie on one line.
text: In order to turn this process into a correlation, the Euclidean plane (which is not a projective plane) needs to be expanded to the extended euclidean plane by adding a line at infinity and points at infinity which lie on this line.
text: K-sets are related by projective duality to k-levels in line arrangements; the k-level in an arrangement of n lines in the plane is the curve consisting of the points that lie on one of the lines and have exactly k lines below them.