Creating a Conchoid of Nicomedes with a given pole, directrix, and distance

Move point F back and forth on the directrix and see how the point G moves. Move point E around to see how the shape changes. Change the length of CD to see how the shape changes. Also check the 'bottom branch' checkbox and study the bottom curve. Change the size of CD and the location of E and determine under what conditions there is a 'loop' in the bottom branch.