Fagnano's problem

          For a given acute triangle determine the inscribed triangle of minimal perimeter.

          This problem was posed by G. Fagnano in 1775. Fagnano's original solution used calculus.
          Here we present two geometric solutions by :

                   Lipot Fejer (1880-1959) and Hermann Schwarz (1864-1951).

          First try to solve the problem yourself. If you need help you could use hints,
         leading you through the Fejer’s solution.
          Then you can see Hermann Schwarz’s solution.