Réponse :
Bonjour
Explications étape par étape
A = -8 +4 X (-3) -6 X (-5) +9
A = -8 -12 +30 +9
A = -20 +39
A = 19
B = (-7 +12) : (4 -3 X 2)
B = 5 : ( 4 -6)
B = 5 : -2
B = -2,5
C = 9 X 7 - ( 5 X (6 -20) +21/7
C = 63 - ( 5 X -14) +3
C = 63 - (-70 +3)
C = 63 - (-67)
C = 63 + 67
C = 130
D = 16 : (2 X 7 -4) = 16 : (10)
8 -15 +2 -5
D = 16/10 X -1/5
D = -16/50 = -8/25
