Conic sections definitions

Circle

Circle

A locus of points in a plane at a fixed distance (r) from a given point (h, k)

Ellipse

A locus of points in a plane for which the sum of the distances from two fixed points (the foci) is constant

Hyperbola

A locus of points in a plane for which the difference of the distances from two fixed points (the foci) is constant

Parabola

A locus of points in a plane that are equidistant from a fixed line (the directrix) and a fixed point (the focus)