Bonsoir,
a)
2x+2x = 8
4x= 8
x = 8/4
x= 2
b)
-8 -4 = 7x -4x
-12 = 3x
x = -12/3
x= -4
c)
5+9 = 6x -3x
14 = 3x
x = 14/3
x
x-10
(x-10) ² = x² -20x +100
x² -20x +100 -x² = -20x + 100
-20x+100 = -340
-20x = -340 -100
-20x = -440
x = -440/-20
x =22
je pense à 22
