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bonjour
3 x + 7 = 5 x + 6
3 x - 5 x = 6 - 7
- 2 x = - 1
x = 1/2
- 2 x - 5 = 6 x - 7
- 2 x - 6 x = - 7 + 5
- 8 x = - 2
x = - 2 /- 8
x = 1/4
8 x - 3 = - 4 x + 12
8 x + 4 x = 12 + 3
12 x = 15
x = 15/12 = 5 /4
bonjour
3 x + 7 = 5 x + 6
3 x - 5 x = 6 - 7
- 2 x = - 1
x = 1/2
- 2 x - 5 = 6 x - 7
- 2 x - 6 x = - 7 + 5
- 8 x = - 2
x = - 2 /- 8
x = 1/4
8 x - 3 = - 4 x + 12
8 x + 4 x = 12 + 3
12 x = 15
x = 15/12 = 5 /4