Répondre :
(x+1) + (x+2) - 2(x+3) = x+1-9
x+1+x+2- 2x-6-x = -8
1+2-6-x = -8
-x = -8-1-2+6
x = 5
(7x-2) - 2(1-2x) = -x +2
7x - 2 - 2 + 4x + x = 2
12x = 6
x = 6/12
x = 1/2
Resoudre et ensuite vérifier le résultat :
(x+1) + (x+2) -2 (x+3) = x+1-9
(7x-2) -2 (1-2x) = -x+2
(x+1) + (x+2) - 2(x+3) = x+1-9
x+1+x+2- 2x-6-x = -8
1+2-6-x = -8
-x = -8-1-2+6
x = 5
(7x-2) - 2(1-2x) = -x +2
7x - 2 - 2 + 4x + x = 2
12x = 6
x = 6/12
x = 1/2