# GeoGebra Tutorial 3 – Constructing a Square

This is the third tutorial of the GeoGebra Intermediate Tutorial Series and the fourth part of the GeoGebra Basic Construction Series. If this is your first time to use GeoGebra, I strongly suggest that you read the GeoGebra Essentials Series.  This tutorial, answers the following problem using GeoGebra.

Problem: How will you draw an equilateral triangle without using the Regular polygon tool?

In this tutorial, we mimic compass and straightedge construction using the Circle tool, the Parallel Line tool, the Perpendicular Line tool of GeoGebra to construct a square instead of using the Regular Polygon tool.  We will also reinforce the use of the Angle tool, this time, learn how to use it to measure angle using three points.

Figure 1 – Square formed from radii of a circle

The idea of our construction is to construct a circle with radius AB and construct lines parallel and perpendicular to it to form our square.

In the tutorial below, menu commands, located in the menu bar, are in brown bold text, and submenus are denoted by the > symbol. For example, Options>Labeling> New Points Only means, click the Options menu, choose Labeling from the list, then select New Points Only. The GeoGebra tools are denoted by orange texts. For example, New Point means the new point tool.