In [b][url=https://www.geogebra.org/m/cddqbunb]Tutorial 2[/url][/b], we have learned to measure objects using the Angle, Slope, and Distance or Length tools. In this tutorial, we learn how to use the [b]Intersect[/b], [b]Line Segment[/b], [b]Circle[/b], [b]Perpendicular line[/b], and[b] Parallel line[/b] tools to construct a square. Try them yourself first (see Expected Output) and if you have difficulties, read the Construction Steps below.

[list=1][*]Select the [b]Line Segment[/b] tool and click on two distinct points to construct line segment [i]AB[/i].[/*][*]To construct the circle with radius [i]AB[/i], select the [b]Circle[/b] tool, click on [i]A[/i] and then click on [i]B[/i]. [/*][*]To construct a line perpendicular to [i]AB[/i] and passing through [i]A[/i], select the [b]Perpendicular Line[/b] tool, and then click on line segment AB and then click on [i]A[/i]. [/*][*]To intersect the circle and the line, select [b]Intersect[/b] tool and then click on the intersection on the upper part. GeoGebra will name this intersection [i]C[/i]. [/*][*]Construct a line perpendicular to [i]AB[/i] and passing through [i]B[/i].[/*][*]To construct a line parallel to [i]AB[/i] and passing through [i]C[/i], select the [b]Parallel[/b] line tool, click on the line segment and then click on [i]C[/i]. [/*][*]Use the Intersect tool to intersect the line parallel to [i]AC[/i] and the line parallel to [i]AB[/i]. GeoGebra will name this point [i]D[/i].[/*][*]Hide everything except line segment AB and then use the[b] Line Segment[/b] tool to complete the square. [/*][/list]