each image below links to a step‑by‑step GeoGebra applet, where you can move forwards and backwards through the construction or watch a short animation of how it unfolds. in some applets, the blue circular points are movable. these applets are also collected in this GeoGebra book.
regular triangle, given the edge
regular triangle, given the diameter of the circuncircle
regular triangle, given the direction of an edge
regular triangle, given the apothem
triangle, given the medial triangle
moving geometry 