Sagot :

Réponse:

Bonjour j'espère que vous allez bien

A3(x+7)=4x+9

= 3×x + 3 × 7 = 4x +9

= 3x + 21 = 4x + 9

= 3 x - 4x = + 9 - 21

= -1x = -12

= -1x/ -1 = 12/-1

B 2(x-4)=7X-2

= 2 × x - 2 × 4 = 7x - 2

= 2x -8 = 7x - 2

= 2x -7x = -2 + 8

= -5x = 6

= -5x/ -5 = 6/ -5