A point is located in a square. Distances are drawn to [u][i][b]either [/b][/i][/u]the sides of the square or to its vertices.[br][br]This applet provides an environment to explore under what circumstances the four distances[br]can form a quadrilateral, and if they can, what can be said about the quadrilateral formed.[br][br][br]Move the yellow point in the left panel to set the four distances. [br][br][br]In the right hand panel choose one of two ways to link the four distances to one another to form a quadrilateral – either [br] [br]BLUE - BLUE - GREEN - GREEN [BBGG] or BLUE - GREEN - BLUE - GREEN [BGBG][br]You can drag the white and black dots to form quadrilaterals.[br][br][[b][i][size=100][size=85]N.B. The yellow dot in the right hand panel allows you to translate the linkage without deforming it.[/size][/size][/i]][/b][br][br]What can you say about the kinds of quadrilaterals that you can form with each linkage of the distances [i.e., to the sides or to the vertices] ? [br][br]Are there quadrilaterals that can be formed with one linkage but not the other?[br][br]Are there quadrilaterals that cannot be formed at all by either linkage ?[br][br][color=#ff0000][i][b]What questions could/would you put to your students based on this applet?[/b][/i][/color][br]