Réponses

2014-05-05T15:52:29+02:00
2x-3=6
2x= 6+3
2x=9
x=9/2
x= 4,5

9x+3=7x-5
9x=7x-5-3
9x=7x-8
9x-7x=-8
2x=-8
x=-8/2
x= -4
2014-05-05T16:46:18+02:00
2x-3=6
2x-3+3=6+3
2x=9
2x/2=9/2
x= 9/2 ou 4,5 (cest pareil)

9x+3=7x-5
9x+3-3-7x=7x-5-3-7x
2x= -8
2x/2= -8/2
x= -4