Avec les outils “stylo” et “distance ou longueur”, on estime la longueur de la corde sur la photo. 
On déterminé ensuite l'échelle grâce au carrelage de côté 16 cm.

Longueur de la corde ≈ 78×16/3 soit 416 cm

A = (-3, -3)
B = (11, -3)
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(the line above was cut: it had 42365 characters; the first 20000 are kept)
Pointtracé1 = Point(tracé)
C = (7.14, 4.22)
D = (10.14, 4.32)
f = Segment(C, D)
Textetracé: "Périmètre de " + (Name[tracé]) + " = " + tracé
Pointtracé = Point(tracé)
L: (78 * 16 / 3)