Ex 1 :
Équation 1:
4x + 7 = 2x + 13
4x - 2x = 13 - 7
2x = 6
x = 6/2
x = 3
Équation 2:
15x = 7x + 4
15x - 7x = 4
8x = 4
x = 4/8
x = 1/2 ou 0,5
Équation 3 :
x - 2 = 10 + 5x
x - 5x = 10 + 2
-4 = 12
x = 12/-4
x = -3
Équation 4 :
7x - 6 = 6x + 3
7x - 6x = 3 + 6
1x = 9
x = 9/1
x = 9
Équation 5 :
-3x - 8 = -7x - 4
-3x + 7x = -4 + 8
4x = 4
x = 4/4
x = 1
Équation 6 :
2x + 5 = 5x + 12
2x - 5x = 12 - 5
-3x = 7
x = 7/-3
x = ~ -2,3
Ex 2 :
Équation 1
4 (5x - 7) = 32
4 X 5x - 4 X 7 = 32
20x - 28 = 32
20x = 32 + 28
20x = 60
x = 60/20
x = 3
Équation 2 :
5 (x + 1) - 3 (x - 2) = 48
5x + 5 X 1 - 3x + 3 X 2 = 48
5x + 5 - 3x + 6 = 48
5x - 3x = 48 - 5 - 6
2x = 37
x = 37/2
x = 18,5
Équation 3 :
3 (2x - 1) - 5x = 3x - 1
3 X 2x - 3 X 1 - 5x = 3x - 1
6x - 5x - 3x = -1 + 3
-2x = 2
x = 2/-2
x = -1
