Réponse :
Bonjour,
1. a)
4/7 :
-4/7 + 8 = 52/7 # -5*4/7 donc non
5:
-5 + 8 = 3 # -5*5 donc non
4/7:
-2+8 = 6 # -5*2 donc non
b) 4*16/49 + 16*4/7 = 64 + 448 / 7 =512/7
6 ( 86 / 7) = 516 / 7 # 512 / 7
Exercice 2.
a) 7x - 10x + 35
-3x = -35
3x = 35
x = 35/3
b) -x - 11 = 22
-x = 33
x = -33
c) -150 - 10x = 9x
-19x = 150
x = -150/19
d) -15x + 15 + 7x = 4
-8x = -11
8x = 11
x = 11/8
e) 7 - (6x + 2 )= 4x - 4
7 - 6x - 2 = 4x - 4
-6x - 4x = -4 + 2 -7
-10x = -9
10x = 9
x = 9/10
f) -3+7x = -10x + 2
17x = 5
x = 5/17
Exercice 3
1)
-5.
-5 + 7 = 2
2* (-6) = -12.
2)
x.
x+ 7
(x+7) * (-6) = -6x - 42
3. On cherche -6x - 42 = 8
-6x = 8+ 42
-6x = 50
x = 50/ -6
Bon courage