Mathématiques

Question

Bonjour , je voudrait de l'aide pour ces équations qui me posent problème :
a. 2(4x-5)=7-(3-x)
b. (5x-2):4 = (3x) :2
c. 7x-3/2=3/4x+5
Voila , merci d'avance

2 Réponse

  • a. 2(4x-5)=7-(3-x)
    a ; 8x-10 = 7-3 +x
    a  8x -x = 4 +10
    a :  7x = 14
    x = 14/7
    x = 2

    b. (5x-2):4 = (3x) :2
    5/4x -2/4 = 3/2x
    5/4x -3/2x = 2/4
    5/4x -6/4x  = 2/4
    -1/4x = 2/4
    x = 2/4 x -4
    x = -8/4
    x = -2

    c. 7x-3/2=3/4x+5
    7x -3/4x = 3/2 +5
    28/4x x -3/4x = 3/2 +10/2
    25/4x = 13/2
    x = 13/2 x 4/25
    x = 52/50
    x = 26/25

  • a. 2(4x-5)=7-(3-x)
    8x -10 = 7-3+x
    8x -x = 4+10
    7x = 14
    x =14/7
    x=2

    b. (5x-2):4 = (3x) :2
    (5x -2) : 4 = 6x/4
    (5x -6x)/4 = 2/4
    -x/4 = 2/4
    -x =2
    x = -2



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