Réponses

2013-11-03T18:00:58+01:00
Bonjour

7x - (5x + 3) = 5 (x-3) + 2 
7x -5x -3 = 5x -15 +2
7x -5x -5x = -15 +2 +3
-3x = -10
x = -10/-3
x = 10/3

 7(n+2) -3 = 25 - (3n + 4)

7n +14 -3 = 25 -3n -4
7n +3n = 25 -4 -14 +3
10n = 10
n = 1


2013-11-03T18:02:37+01:00
7x-5x-3=5x-15+2
7x-5x-5x=3-15+2
-3x=-10

7n+14-3=25-3n-4
7n+3n=-14+3+25-4
10n=10