Réponse :
bonjour
4 x = 12
x = 3
- &r = ?
x + 8 = 15
x = 15 - 8
x = 7
x- 5 = 15
x = 20
3 x - 7 = 23
3 x = 30
x = 10
- 3 r + 2 = - 19
- 3 r = - 19 - 2
- 3 r = - 21
r = 7
5 x - 8 = - 10
5 x = - 10 + 8
5 x = - 2
x = - 2/5
4 x - 7 = 2 x + 13
4 x - 2 x = 13 + 7
2 x = 20
x = 10
- Gr ?
- 7 x + 8 = - 4 x + 12
- 7 x + 4 x = 12 - 8
- 3 x = 4
x = - 4/3
( 3 x - 6 ) ( 2 x + 8 ) = 0
x = 6/3 = 2 ou x = - 8/2 = - 4
( 5 x - 10 ) ( 3 x + 15 ) = 0
x = 10/5 = 2 ou x = - 15/3 = - 5
x ( 3 x - 7 ) ( - 2 x + 4 ) = 0
x = 0 ou x = 7/3 ou x = - 2
( 6 x - 7 ) ( - 3 x - 9 ) = 0
x = 7/6 ou - 3
r = 16
x = 15
19 + x² = 100
x² = 100 - 19
x² = 81
x = √81 ou - √81
x = 9 ou - 9
3 x² = 27
x² = 9
x = √9 ou - √9
x = 3 ou - 3
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