The six sides of a cyclic hexagon PQRSTU are PQ, QR, RS, ST, TU and UP. It is known that PQ= RS= TU and the diagonals PS, QT and RU meet at the point V. The lines PS and RT intersect at the point W.

Determine the ratio RW/WT, given that PR = 3*RT.

                         .  . .  .  . .  .
                    .                         .
                 .                               .
              .                                     .
            .                                         .
          .                                             .
        .Q                                              R .
       .                                                   .
      .                                                     .
     .                                                       .
    .                                                         .

   .                                                           .
   .                                                           .
   .                                                    V     WS
   P                                                           T
   .                                                           .

    .                                                         .
     .                                                       .
      .                                                     .
       .                                                   .
        .                                                 .
          .                                             .
            .                                         .U
              .                                     .
                 .                               .
                    .                         .
                         .  . .  .  . .  .

Unfortunately the reader must visualise the lineal connections.

It's easy to find the ratio if you know that PU = QR. Playing around with Geometer's Sketchpad, the givens of the problem seem to force PU to equal QR. I'm still trying to prove it.

Posted by Bractals on 2007-12-09 03:45:26