## Conic Sections - Circles, Ellipses, Parabolae and Hyperbolae

Circles, ellipses and hyperbolae have similar equations: All these curves are obtained from the intersection of a plane with a cone as shown above.

for a circle of ellipses centred at the origin, withfor a circle andfor an ellipse andfor a circle or ellipse centred at

For a hyperbola,centred at the origin or for a hyperbola centred atat with again

are all equations of parabolae.