Réponses

  • x22
  • Modérateur Junior
2014-09-20T15:17:08+02:00
Salut!

A=7 x 8 + 9 x (-9) + 3)
=56+9x(-9)+3
=56+(-81)+3
=56-81+3
=-25+3
=-22

B=
7 x 8 + 9 x (-9+3)
=56+9x(-9+3)
=56+9x(-6)
=56+(-54)
=56-54
=2

C=
(12,5-4) x (5,8-4,2)
=(8,5)x(1,6)
=13,6

D=
12,5 - 4 x (-5,8) - 4,2
=12,5-(-23,2)-42
=12,5+23,2-42
=35,7-42
=-6,3

Voilà
2014-09-20T15:20:10+02:00
A=7×8+9×(-9)+3=140
B=7×8+9×(-9+3)=110
C=(12,5-4)×(5,8-4,2)=13,6
D=12,5-4×(-5,8)-4,2=31,5