Réponse:
A = [-5-(-8)]×(-2)
A = (-5+8)×(-2)
A = -2x(-5)+(-2)×8
A = 10+(-16)
A = 10-16
A = -6
B = 26-(-9)×1,5-0,5
B = 26+9×1,5-0,5
B = 26+13,5-0,5
B = 26+13
B = 39
C = 39÷[-3+2×(8-4×1)-4×(9÷2)]
C = 39÷[-3+2×8+2×(-4)-4×4,5]
C = 39÷[-3+16+(-8)-18]
C = 39÷(-3+16-8-18)
C = 39÷(-13)
C = -3
Bonne soirée :)