Résoudre ces équations : -->  5x + 89 - 57 + 4x = 58 - 69 + 2x --> 825 - 877 + 6x + 8 = 225 - 85 + 6x --> 14 + 48 + 6x =  17x + 5 - 9x --> 54 - 99 - 6 + 4x = 54

5x + 89 - 57 + 4x = 58 - 69 + 2x
<=> 5x + 4x - 2x = 58 - 69 - 89 + 57
<=> 7x = -43
<=> x = -43/7
S={-43/7}

825 - 877 + 6x + 8 = 225 - 85 + 6x
<=> 6x - 6x = 225 - 85 - 825 + 877 - 8
<=> 0 = 214
IMPOSSIBLE.

14 + 48 + 6x =  17x + 5 - 9x
<=> 6x + 9x - 17x = 5 - 14 - 48
<=> -2x = -57
<=> x = 57/2
S={57/2}

54 - 99 - 6 + 4x = 548 + 65 + 8x
<=> 4x - 8x = 548 + 65 - 54 + 99 + 6
<=> - 4x = 664
<=> 4x = -664
<=> x = -664/4
<=> x = -166
S={-166}

salut :)

5x + 89 - 57 + 4x = 58 - 69 + 2x
9 x+32 = 2 x-11
x = -43/7

( 825 - 877 + 6x + 8 = 225 - 85 + 6x ) cette équation  et faute en ecriture il n'a pas une soulution 
6 x-44 = 6 x+140

14 + 48 + 6x =  17x + 5 - 9x
6 x+62 = 8 x+5
x = 57/2

54 - 99 - 6 + 4x = 548 + 65 + 8x
4 x-51 = 8 x+613
x = -166