Left: The perspectrix of T, T is perpendicular to the Euler Line of T . Right: The perspectrix of T, T is perpendicular to the line through X4 and X671.
The Negative Pedal Curve (NPC) of the Ellipse with respect to a boundary point M is a 3-cusp closed-curve which is the affine image of the Steiner Deltoid. Over all M the family has invariant area and displays an array of interesting properties.
LIPOID PROTIENOSIS INTRA CRANIAL CALCIFICATIONS