-1 8 setxrange
-1 9 setyrange
150 setheight
quadrillage
/A {0 0} def
/B {7 0} def

/cerc1 {A 9} def
/cerc2 {B 8} def
cerc2 cerc1 intercercle /C defpoint popp

B C C 4.5 interdroitecercle 
popp
/I defpoint

B C C 4.8 interdroitecercle 
popp
/J defpoint


A C 10 Arc
B C 10 Arc

[A B C] polygone

.6 setlinewidth
[I A J] ligne

[A B C I J] points

setTimesItalic
   (A) A dltext
   (B) B drtext
   (C) C urtext
   (I) I urtext
   (J) J urtext