bonjour aider moi svp, Résoudre les équations suivantes : a) 2(3x + 1) - 3 = x + 9 b) (3x-6)(-2x +14) = 0 d) 2x² + 11 = 1 c) x² = 15​

Réponse:

a) 2(3x+1)-3 = x +9

6x + 2 -3 = x +9

6x -x = 9 +3 -2

5x = 10

5x/5 = 10/5

x = 2

b) (3x-6)(-2x+14) = 0

3x -6 = 0

3x = 6

3x/3 = 6/3

x = 2

-2x+14 = 0

-2x = -14

-2x/-2 = -14/-2

x = 7

L'équation a deux solutions : 2 ou 7

c) 2x²+11 = 1

2x² = 1 -11

2x² = -10

2x²/2 = -10/2

x² = -5

√x² = √-5

x = √-5

d) x² =15

√x² = √15

x = √15