Assertion: ellipse | /r/DefinedAs | the envelope of all lines
Facets:
value: by projective duality
type: OTHER
Source sentences:
text: By projective duality, an ellipse can be defined also as the envelope of all lines that connect corresponding points of two lines which are related by a projective map.
text: By projective duality, an ellipse can be defined also as the envelope of all lines that connect corresponding points of two lines which are related by a projective map.