%% taille de la fenetre
-0.5 5.5 setxrange
-0.5 3.5 setyrange
28.346 setxunit
%% definition des points
/A {0.6 3} def
/C {5 0} def
/B {0 0} def
[A B C] polygone
/P  {B A 0.333 hompoint} def
/P1 {B A 0.666 hompoint} def
/M1 {B C 0.2 hompoint} def
/M2 {B C 0.4 hompoint} def
/M  {B C 0.6 hompoint} def
/M4 {B C 0.8 hompoint} def
/N {C A 0.25 hompoint} def
/N1  {C A 0.5 hompoint} def
/N2 {C A 0.75 hompoint} def
[A B C P P1 M1 M2 M M4 N N1 N2] points

pointilles
[A M] ligne
[B N] ligne
[C P] ligne

setTimesItalic
   (A) A ultext
   (B) B dltext
   (C) C drtext
   (P) P ultext
   (M) M dtext
   (N) N urtext