bjr
ex 43
5x + 7 = 2x - 2
but du jeu : les x à gauche et les constantes à droite
explication complète :
5x + 7 - 7 = 2x - 2 - 7
5x = 2x - 9
5x - 2x = 2x - 2x - 9
3x = -9
3x/3 = -9/3
x = - 3
3x + 2 = x - 10
3x + 2 - 2 = x - 10 - 2
3x = x - 12
3x - x = x - x - 12
2x = -12
2x/2 = -12/2
x = - 6
44
2x - 5 = 5x + 1
2x - 5x = 1 + 5
-3x = 6
x = -2
et
3 - 7x = 3x + 2
-7x - 3x = 2 - 3
- 10x = -1
x = 1/10
