Bonjour j'ai besoin d'aide pour l exercice 1 svp

Bonjour


♧ Exos 1 :

6x + 9 = -3
6x = - 3 -9
6x = -12
x = -12/6 d'où x = - 2

6x - 31 = 4x + 9
6x - 4x -31 = 9
2x = 9 + 31
2x = 40
x = 40/2 d'où x = 20

Voilà ^^

Bonjour,

6x + 9 = -3
6x = -3 - 9
6x = -12
x = -12/6
x = -2

6x - 31 = 4x + 9
6x - 4x = 31 + 9
2x = 40
x = 40/2
x = 20

A = 4(5n - 9)
A = 4 * 5n + 4 * (-9)
A = 20n - 36

B = (7x + 5)(3x - 8)
B = 7x * 3x + 7x * (-8) + 5 * 3x + 5 * (-8)
B = 21x^2 - 56x + 15x - 40
B = 21x^2 - 41x - 40