%!

/i47 {
1 dict begin
/b exch def
/a exch def
/c a dup mul b dup mul add sqrt def
0 0 moveto
b a atan rotate
a 0 lineto
b a atan neg rotate
c 0 lineto
closepath

end
} def

% -------------------------------------------------

72 dup scale
1 72 div setlinewidth

2 4 translate

newpath
  3 4 i47 
stroke