Jute twine ellipses Locus of a point All points in a plane Sum of the distances, two fixed points lane Foci is constant Circle special form of an ellipse Both foci are at the center Major axis, longest segment across the ellipse, connect two vertices
Ellipse x2a2+y2b2=1 x 2 a 2 + y 2 b 2 = 1 .
Circle with centre x2 + y2 + 2gx + 2fy + c = 0, represents the circle with centre (−g,−f) and radius equal to a2 = g2 + f2− c