bonjour
- 4 * 2 = - 8
- 8 + 3 = - 5
5 x 2 = 10
10 + 3 = 13
x * 2 = 2 x
2 x +3
b ) 2 x + 3
pour x = - 1 = - 2 + 3 = 1
2 x + 3 = 8
2 x = 8 - 3
2 x = 5
x = 5/2 = 2.5
- 5 x + 9 = 2
- 5 x = 2 - 9
- 5 x = - 7
x = 7/5
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6 x - 9 = 12 - 3 x
6 x + 3 x = 12 + 9
9 x = 21
x = 21/9 = 7/3
a) 2 x - 3 = 4 - x
2 x + x = 4 + 3
3 x = 7
x = 7 /3 donc oui
b ) 2 x - 3 = 6 - x
2 x + x = 6 + 3
3 x = 9
x = 9 /3 = 3 donc non
c ) 6 x + 3 x = 12 + 9
9 x = 21
x = 21/9 = 7/3 donc oui
d) 9 x - 9 = 12
9 x = 12 + 9
9 x = 21
x = 21/9 = 7 /3 donc oui
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5 x - 2 = - 7
5 x = - 7 + 2
5 x = - 5
x = - 1
9 x - 64 = - 1
9 x = - 1 + 64
9 x = 63
x = 7
Explications étape par étape
