T5d = split a regular triangle in 5 equal area pieces with minimum perimeter. Not best solution known.
      origin of coordinates:  in the middle of the base
      if there are symmetries in the solution the data are given only for the significant part

border
     (0, sqrt(3)/2)
     (+0.5, 0)
     (-0.5, 0)

vertex 1    ( 0.128891563, 0.275493049)
     arc 11 (-0.976407118,           0) 1.139114390  [centercoordinates and radius]
     arc 12 (           0,-0.173876870) 0.467489422  [centercoordinates and radius]
     arc 13 ( 0.656325231,-0.270763243) 0.759330107  [centercoordinates and radius]

separated arc
     arc 22 (           0,   sqrt(3)/2) 0.406692351  [centercoordinates and radius]

yields the following cutlength
     CL = 1.614520955