This is a quadrilateral created using GeoGebra. The first step is to click the segment line and create AB. Next, construct two lines perpendicular to segment AB and passing through A and B. Selected the perpendicular line tool, then select point A and then select perpendicular line then a line will extend from A. Now click the perpendicular line again then click on the line between AB and then drag the line to point B (should be extending through B). To get the next point select the point tool then click above point B to get point C. Now we need to construct a line parallel to AB and passing through C. Select the parallel line tool and select parallel line then click on AB and drag line up through C then click on point C. The next step is two select the intersect two objects and then click the two lines of intersect (line through A and line at top through point C. Finally label point D and hide lines, then reconnect points with the segment line tool.