Get the Cardioide by tracing a circle! This cardioide is the locus of a circle which center moves around another circle.

This Cardioide (animate when you open the file) results as the trace of a point in a circle which is sliding around a given circle

A Parabola - Choose three points that are noncolinear. AB will be the directrix (make A and B stand quite apart) and C the focus. Move C from one side of the line AB to the other to see what happens!

An Elipse or a Hyperbola - A and C are the focus. If you choose AC<AB you get an Elipse; If you choose AC>AB you get a Hyperbola. Move C around in your sketch to check it out!

For a given triangle:

Centers of the Triangle - Click in each of the following for the:

The Circumcenter: C

The Orthocenter: H

The Incenter: I

The Centroid: G

The Chig to get all of the centers.


Special triangles - Click in the following for the:

Medial Triangle

Orthic Triangle

Pedal Triangle - Is constructed in relation to the Pedal Point P.

Shrinked Medial Triangle


Special Circles - Click in the following for the:


Excircles - The point T and U are the extremes of an auxiliary segment; A, B and C are the vertices of the triangle for which the excircles are constructed.

Nine point Circle


The points one has to select before running the scripts are the three vertices.

Move the relative position of the vertices if the picture does show what was promised.


To draw a pentagran inscribed in a given circle.

To trissect a segment

To draw the circles tangent to two given circles and at a given point in one of the circles.

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