Bonsoir, voici mes raiponces.
Réponse :
a) x = 14/3
b) x = -14/3
c) x = -4/3 où x = 7
d) x = 1/7
e) x = racine carré de 11
f) x = 6/5 où x = 0
g) x = -20/9
Explications étape par étape
a)
3x - 9 = 5
3x = 5 + 9
3x = 14
x = 14/3
b)
7(2x - 4) = 20x
14x - 28 = 20x
14x - 20x = 28
-6x = 28
-x = 28/6
x = -28/6
x = -14/3
c)
(7 - x ) (3x + 4) = 0
x = -4/3 où x = 7
d)
2x + 3 = -5x + 4
2x + 5x = 4 - 3
7x = 1
x = 1/7
e)
4x² = 44
x² = 44/4
x = racine carré de 44/4
x = racine carré de 11
f)
2x (5x -6) = 0
x = 6/5 où x = 0
g)
-x - 7 = 8x + 13
-x - 8x = 13 + 7
-9x = 20
-x = 20/9
x = -20/9
