How to create a perfect rectangle without using a tape measure or square.

This method of rectangle construction works for laying out large pads, landscaping etc. You can use a tape measure if you desire a rectangle or square with specific dimensions (a square is just a subcategory of a rectangle).

This rectangle construction method relies on the propertied of quadrilaterals. If the diagonals of a quadrilateral are equal and they bisect each other the quadrilateral will always be a rectangle. It is NOT possible to construct a figure with those two properties that will be anything but a rectangle with two sets of parallel sides and 4 90 degree corners.

This method also works on smaller rectangles but in those cases there are easier methods that are just as accurate.

[dpm]

Thanks for this easy to understand example. However, I believe a parallelogram's diagonals don't equal unless it's a rectangle. Every rectangle is a parallelogram, but not every parallelogram is a rectangle. A parallelogram that's not a rectangle will not have diameters that are equal.