Mathématiques

Question

Bonjour, pouvez vous m’expliquez comment résoudre ces équations, merci d’avance
7-3x=-8
9x-4=5x+8
5(2x+4)=7

2 Réponse

  • Bonjour,

    7-3x=-8

    - 3x = - 8 - 7

    - 3x = - 15

    x = 15/3

    x = 5

    9x-4=5x+8

    9x - 5x = 8 + 4

    4x = 12

    x = 12/4

    x = 3.

    5(2x+4)=7

    10x + 20 = 7

    10x = 7 - 20

    10x = - 13

    x = - 13/10.

    x = - 1,3.

  • Bonjour,

    7 - 3x = - 8

    7 + 8 = 3x

    15 = 3x

    15/3 = x

    5 = x

    9x - 4 = 5x + 8

    9x - 5x = 8 + 4

    4x = 12

    x = 12/4 = 3

    5(2x + 4) = 7

    10x + 20 = 7

    10x = 7 - 20

    10x = -13

    x = -13/10 = - 1,3

Autres questions