I have a strip of paper with parallel sides, a pencil and a straight edge.
How can I construct a regular pentagram (star) with these? And for that matter, a pentagon? Well ... the pentagon is the proper way to go.
(In reply to A trick
by Brian Smith)
It occurs to me that this would require a strip of "sufficient" length. For example, if the strip is 2 inches x 3 inches, one might find it difficult to knot and flatten it.
I suppose one could fold it lengthwise once or twice to make it more "longer" than "wider".
So, how much longer (what ratio?) must the length be, than the width, to be able to accomplish your method?