Réponses

2013-05-19T18:03:03+02:00

25x - 12 = 3 + 20x

25x - 20x = 3 + 12

5x = 15

x = 15/3

x = 3

 

4t - 1 = 5 - 2t

4t + 2t = 5 + 1

6t = 6

t = 6/6

t = 1

 

10 + 12y = 7y - 5

12y - 7y = -5 - 10

5y = -15

y = -15/5

y = -3