bonjour
8 - ( 3 x - 8 ) = - 8 x - 1
8 - 3 x + 8 = - 8 x - 1
- 3 x + 8 x = - 1 - 8 - 8
5 x = - 17
x = - 17/5
13 x + 6 = 8 x - 1
13 x - 8 x = - 1 - 6
5 x = - 7
x = - 7 /5
9 x - 63 = 3 x - 3
9 x - 3 x = - 3 + 63
6 x = 60
x = 10
11 x + 9 = x + 8
11 x - x = 8 - 9
10 x = - 1
x = - 1 /10
1 ) 2 x = 10 - 4
2 x = 6
x = 3
prix d'un k = 3 €
2 ) 9 ( x + 3 ) = 6 ( x + 7 )
9 x + 27 = 6 x + 42
9 x - 6 x = 42 - 27
3 x = 15
x = 5
ils ont choisi 5
3 ) 7 ( x + 2 ) = 6 x + 6
7 x + 14 = 6 x + 6
7 x - 6 x = 6 - 14
x = - 8
ils ont choisi - 8
4 ) 3 x + 7.4 = 20.6
3 x = 20.6 - 7.4
3 x = 13.2
x = 4.4
la longueur d'un côté = 4.4 cm
