# Construct an Inscribed Quadrilateral in the Hyperbolic Disk

Using the tools in the toolbar the below, inscribe a regular quadrilateral in the given circle. You might call this a "square" because it has four sides of the same length, and all angles are the same measure. Of course, none of the angles are right angles, so it isn't a square in the usual sense; there are no quadrilaterals with four right angles in hyperbolic geometry.

You should have already completed the midpoint problem, so that you are familiar with how to use the tools. As in the Euclidean octagon problem, you have extra tools to construct perpendiculars, find midpoints, and bisect angles (you may not need all of these). Try moving the points A and O around to get a better feeling for how the figure can vary.

After you have successfully made the construction, enter the password you get at the bottom of the page so I can give you credit.
This page requires a java-enabled browser for correct functioning. If you can't get it to work, you can do the construction with other software such as Geometer's Sketchpad or NonEuclid. Pencil and paper might be tricky. It is easier for me if you can get this to work, of course, since then the computer grades it.

Please enable Java for an interactive construction (with Cinderella). Please enable Java for an interactive construction (with Cinderella).
Please enable Java for an interactive construction (with Cinderella).
enter your Last Name Stony Brook ID and the password then click .

Java exercise created using Cinderella for MAT 360 by Scott Sutherland on April 20, 2004.