Mathématiques

Question

help ex 35 et 37! avec calcul si possible! merci d'avance
help ex 35 et 37! avec calcul si possible! merci d'avance

1 Réponse

  • 35)
    a) x - 1 = 1/6
    6x/6 - 6/6 = 1/6
    6/6x = 1/6 + 6/6
    6x = 7
    x = 7/6

    b) 3x - 2 = 4/3
    9/3x - 6/3 = 4/3
    9/3x = 4/3 + 6/3
    9x = 10
    x = 10/9

    c) 2/5x + 1 = 4/5
    2/5x + 5/5 = 4/5
    2/5x = 4/5 - 5/5
    2x = - 1
    x = - 1/2
    x = - 0,5

    d) 3/7x + 4 = - 8
    3/7x + 28/7 = - 56/7
    3x= - 56 - 28
    3x = - 84
    x = - 84/3
    x = - 28

    37)
    a) 3 (x- 1) + 2 (x + 3) = 0
    3x - 3 + 2x + 6 = 0
    3x + 2x = 3 - 6
    5x = - 3
    x = - 3/5
    x = - 0,6

    b) - 5 (x + 2) + 3 (x - 3) = 7
    - 5x - 10 + 3x - 9 = 7
    - 5x + 3x = 7 + 10 + 9
    - 2x = 26
    x = - 26/2
    x = - 13

    c) 4 (- x + 1) - 2 (3x - 5) = 0
    - 4x + 4 - 6x + 10 = 0
    - 4x - 6x = - 10 - 4
    10x = 14
    x = 14/10
    x = 1,4