bonjour,
GD+C = 137kg
GD+F = 143kg
F+C = 32kg
GD+F = 143kg
C+F = 32kg
on peut écrire ds C+F = 32kg :
F = 32-C
on remplace F ds GD+F = 143kg
GD+32-C = 143kg
GD-C = 143-32 = 111kg
on sait que GD+C = 137kg
GD+C = 137kg
GD-c = 111kg
2GD = 248kg
GD = 124KG
GD+C = 137kg
124+C = 137kg
C = 137-124 = 13kg
F+C = 32kg
F+13 = 32kg
F = 19KG