le 84 et le 85 svp !!! c'est pour demain

EX 84 :

A = 3x + 12 

A = 3(x + 4)

B = 9x + 15

B = 3(3x + 5)

C = 6x - 6

C = 3(2x - 2)

D = 36x + 6

D = 3(12x + 2)

EX 85

A = 2x + 2*3

A = 2x + 6

A = 2(x + 3)

B = 5*4 - 5x

B = 20 - 5x

B = 5(4 - x)

C = 7x + 21

C = 7(x + 3)

D = 26 - 13x

D = 13(2 - x)

Exercice 84.

mettre 3 en facteur

3x +12 = 3(x+4)

9x +15

3(3x + 5)

6x -6 = 3(2x -2)

36x +6

3( 12 x +2)

Exercice 85

factorisation

2x +2 X 6

2x +6

2(x +3)

5 X 4 -5x = 

20 -5x

5(4 -x)

7x +21 = 7(x +3)

26 -13x = 13( 2-x)