Réponses

2014-06-03T22:03:32+02:00
X+3 < 12
x < 12-3
x < 9

7x > 21
x > 21/7
x > 3

3/4 x < 1/4
4* 3x/4 > 4*1/4 (* signifie multiplié par)
3x > 1
x > 1/3

-5/8 x > 3/4
5/8 x < -3/4
5x < -3*8/4
5x < -3*2
5x < -6
x < -6/5

4x +7 > 6x-5
4x -6x +7 > -5
-2x > -5-7
-2x > -12
2x < 12
x < 12/2
x < 6