Bonjour pouvez vous m'aider svp merci : Trouvez x a) -2 -5 (-6 + -3x / -5) = -4x + (-6x+2) b) 2/5 = 9 / 8 + x c) 7 + (5/4)x = 3/2 Merci de votre aide

Bonjour,

a) -2 -5 (-6 + -3x / -5) = -4x + (-6x+2)

- 2 + 30 - 15x/5 = - 4x - 6x + 2

- 2 + 30 - 3x = - 4x - 6x + 2

- 3x + 4x + 6x = 2 + 2 - 30

7x = - 26

x = - 26/7

b) 2/5 = 9 / 8 + x

- x = 9/8 - 2/5

- 40/40x = - 45/40 - 16/40

- 40x = - 29

x = 29/40

c) 7 + (5/4)x = 3/2

5/4x = 3/2 - 7

5/4x = 6/4 - 28/4

5x = 6 - 28

5x = - 22

x = - 22/5