the following links direct to:

curves

• right strophoid
• cardioid

conics

• tangents to a circle, from an exterior point
• tangents common to two equal circles
• tangents common to two different circles
• interior tangents common to two different circles
• ellipse, given its axes #01
• ellipse, given its axes #02
• tangent and normal to the ellipse
• foci of a given ellipse
• tangents to an ellipse, from an exterior point
• tangent to an ellipse, given its direction