Réponse :

a. 2(4x-5)=4+x

6x - 10 = 4 + x

6x-x = 4+10

5x=14                  x=14/5

b. 2(x+8)+3=4-3x

2x + 16 + 3 = 4 - 3x

2x + 3x = 4 - 19

5x = -15                      x=-15/5=-3

c. 12x - 1 = 2(5x-2)+1

12x - 1 = 10x - 4 + 1

12x - 10x = -3 + 1 = -2

2x = -2                              x=-2/2=-1

d. (x-3)² =x(x-5)

*x-3=0       x=3

*x-5=0       x=5

*x=0

Explications étape par étape :

Réponse :

a. 2(4x - 5) = 4 + x

8x - 10 = 4 + x

7x = 14

x = 2

b. 2(x + 8) + 3 = 4 - 3x

2x + 16 + 3 = 4 - 3x

2x + 19 = 4 - 3x

5x = -15

x = -3

c. 12x - 1 = 2(5x - 2) + 1

12x - 1 = 10x - 4 + 1

12x - 1 = 10x - 3

2x = -2

x = -1

d. (x - 3)^2 = x(x - 5)

x^2 - 6x + 9 = x^2 - 5x

-x = -9

x = 9