Pour l’exercice 3 :
Partie 1)
-45 = 9x(-5) // -36 = (-2)x(-6)x(-3)
Partie 2)
A= (-7-3)x(-5)
= (-10)x(-5)
=50
B= -7x5-2x(-3)
= -35 -(2x-3)
= -35 -(-6)
= 35 +6
= -29
C= 23-(7-9)x(-10)
= 23-(-2 x -10)
= 23 -(20)
= 3
Partie 3)
a) -15 = 3x (-5)
b) -15 = (-1)x 3x5
c) -15 = -20+5
d) -15 = -10-5
e) -15 = -30:2
