Each of the images below is a link to a step-by-step GeoGebra applet through which it is possible to move forwards and backwards in the construction, or watch how the construction is solved in a short animation. The blue “circular” points in some applets are movable.

These applets are gathered in this this GeoGebra book.

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regular pentagon inscribed in a circle #01

regular pentagon inscribed in a circle #02

regular pentagon inscribed in a circle #03

(adapted from the marvelous book A Geometria ao Alcance de toda a Gente (1947), authored by A. A. Ferreira de Macedo.

regular pentagon inscribed in a circle #04

regular pentagon given the edge length

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