Réponse :
1ère ligne :
b-c = 6-4 = 2
a-(b-c) = 8-(6-4) = 6
(a-b) = (8-6) = 2
2ème ligne :
b-c = -6-(-3) = -3
a-(b-c) = 1-(-6-(-3)) = 4
(a-b) = (1-(-6)) = 7
3ème ligne :
b-c = 13.5-4.5 = 9
a-(b-c) = -9-(13.5-4.5) = -18
(a-b) = (-9 -13.5) = -22.5
4ème ligne :
b-c = -8-(-15) = 7
a-(b-c) = -7-(-8-(-15)) = -14
(a-b) = (-7-(-8)) = 1
