Keywords: Ellipse Properties of Directrix.svg ellipse including<br> The constant of proportionality is the eccentricity e D called the directrix The ratios e f/a a/d PF/PD are always constant The eccentricity is always between 0 and 1 At zero the ellispe becomes a circle at 1 the ellipse becomes a parabola Greater than one it is a hyperbola <br> Other related images <br> 150px 150px <br> These images were edited with the free open source program Inkscape Ellipse_Properties svg 2010-07-02 19 03 UTC Ellipse_Properties svg Inductiveload derivative work Dave3457 <span class signature-talk >talk</span> derivative work ElectroKid <small> </small> Inkscape 34555 1423 U Krishnavedala Removed all information but the directrix Note the location of the foci ect were off on the original Ellipse_Properties svg Ellipses |