Réponse:
a) 3x +5 = 4x -7
3x -4x = -7 -5
-x = -12
x = 12
b) 2x -9 = 8x +3
2x -8x = 3 +9
-6x = 12
-6x/-6 = 12/-6
x = -2
c) -2x +3 = 3x -1
-2x -3x = -1 -3
-5x = -4
-5x/-5 = -4/-5
x = 4/5
e) 1 +x = 4 -x
x +x = 4 -1
2x = 3
2x/2 = 3/2
x = 3/2
f) x2 +3x -2 = 7x +4 + x7
5x -2 = 14x +4
5x -14x = 4 +2
-9x = 6
-9x/-9 = 6/-9
x = 2/-3
Explications étape par étape:
je pense que c'est vrai , Bon courage :)