Constantinople (x1), Tehran (x2), Madrid (x3), and Rome (x4) lie on the same straight line (great circle). The values representing their relative positions are encoded in the roots of a depressed quartic equation that is solved geometrically.
Constantinople (x1), Tehran (x2), Madrid (x3), and Rome (x4) lie on the same straight line (great circle). The values representing their relative positions are encoded in the roots of a depressed quartic equation that is solved geometrically.