%% auteur : Florent Braisaz

-4.9 4.9 setxrange
-4.9 4.9 setyrange
15 setxunit
15 setyunit

/A {-3.5 -3.5} def
/B {-1 2} def
/C {3.5 -3.5} def
/M {A C milieu} def

1.25 setlinewidth

[A B C] polygone

gsave
rouge
B M droite
[M A M C]{2 marked} dapply
#latex# ${\Delta}$ 
-1.5 3.5 [1.5 dup] urtexlabel
grestore


gsave
setTimesItalic
(A) A [1.5 1.5] cltext
(B) B [1.5 1.5] urtext
(C) C [1.5 1.5] crtext
(M) M [1.5 1.5] dltext
grestore