Constructing a perpendicular line to a given line...
Source:
February 12, 2011
geometry unsolvedgeometry
Problem Statement
A round coin may be used to construct a circle passing through one or two given points on the plane. Given a line on the plane, show how to use this coin to construct two points such that they de ne a line perpendicular to the given line. Note that the coin may not be used to construct a circle tangent to the given line.