Réponses

2013-10-25T15:29:47+02:00
A= 2(3+x)+(2+x)*4
=6+2x+8+4x
=6x+14
Donc le B maintenant:
B=2(3+x)+(5+2(x-1))
=6+2x+(5+(2x-2)
=6+2x+(5+2x-2)
=6+2x+(2x+3)
=6+2x+2x+3
=4x+9
Voilà ^^