User talk:2601:600:897F:EDC8:356D:1B6D:D285:D40

Main article: https://en.wikipedia.org/wiki/Constructible_number Something is wrong with the middle diagram under the heading "Compass and straightedge constructions for constructible numbers". Note the setup for diagram 1 and diagram 2 are the same, yet they come up with different values for CD and BD.