Bonjour Pourriez vous m'aider svp ???
Mathématiques
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Question
Bonjour Pourriez vous m'aider svp ???
1 Réponse
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1. Réponse maudmarine
Bonjour,
a) 6 (3y - 5) = - (- 5 - y)
18y - 30 = 5 + y
18y - y = 5 + 30
17y = 35
y = 35/17
b) - (18 - x) + 7 (3x + 5) = - (2 - 4x)
- 18 + x + 21x + 35 = - 2 + 4x
x + 21x - 4x = - 2 + 18 - 35
18x = - 19
x = - 19/18
c) (3x + 9) (x - 2) = 0
3x + 9 = 0 ou x - 2 = 0
3x = - 9 x = 2
x = - 9/3
x = - 3
d) 9x² - 36 = 0
(9x - 18) (x + 2) = 0
9x - 18 = 0 ou x + 2 = 0
9x = 18 x = - 2
x = 18/9
x = 2
e) x² - 169 = 0
(x - 13) (x + 13) = 0
x - 13 = 0 ou x + 13 = 0
x = 13 x = - 13.