28.4527 setxunit %% 10 mm
%60 setxunit
0 8 setxrange
0 4 setyrange

%[1 1 .5 .5 .1 .1] {orange} Quadrillage

%tracerepere

/O {2 1} def
/cer {O 2.5} def
/A {-5 cer cpoint} def
/B {45 cer cpoint} def
/I {20 cer cpoint} def
/J {A B O I interdroite} def


O I droite
O A (->) line
O B (->) line
B A (->) line
O J B angledroit