5) 3 x+4=−7−2 x 6) 3x+4=4x–1 7) 13 x−30=7 x – 14 8) 2(x+1)+3(x−1)=0 Niveau 3ème Aidez moi

Bonjour,

5) 3 x+4=−7−2 x

3x + 2x = - 7 - 4

5x = - 11

x = - 11/5

6) 3x+4=4x–1

3x - 4x = - 1 - 4

- 7x = - 5

x = 5/7

7) 13 x−30=7 x – 14

13x - 7x = - 14 + 30

6x = 16

x = 16/6

x = 8/3

8) 2(x+1)+3(x−1)=0

2x + 2 + 3x - 3 = 0

2x + 3x = - 2 + 3

5x = 1

x = 1/5.