Bonsoir,
G=
6x +2x² +3 +x= 2x² +7x+3
H=
4x² -x +20x -5 = 4x² =19x -5
I=
x² +5x -x -5 = x² +4x -5
J=
x² -6x -5x +30 = x² -11x +30
K=
-14x² +35x -2x +5= -14x² +33x +5
L=
12x² -8x -15x +10 = 12x² -23x+10
M=
97z + 9 991
N=
8a -32
0=
7-x +3 = -x +10
P=
x+3 -4 -x= -1
Q=
3-2 -t -2t = 1 -3t
R=
2-u -3 +u = -1
