Bonsoir svp exercices 20 à 22

Réponse:

EX 20)1/4x - 1 =1/2

1/4x=1/2+1

1/4x=3/2

x=3/2×4

x=12/2

x=6

x+1/8=3/4x_3

x_3/4x =-3_1/8

1/4x=_24/8_1/8

1/4x=_25/8

bonsoir

x/4  - 1   = 1/2

x/4 = 2/4 + 4/4

x /4 = 6 /4

4 x = 24

x = 6

x + 1/8  = 3 x / 4 - 3

8 x / 8  - 6 x / 8 = -  1/8 - 24/8

2 x  /8 = - 25 / 8

2 x  = - 25

x = 25/2 = 12.5

x + 3 = - 3 x + 7

x + 3 x = 7 -  3

4 x = 4

x = 1

3 x-  8 = - 1

3 x =  - 1 + 8

3 x = 7

x = 7/3

1 / ( x + 2) = 2 /3

2 x + 4 = 3

2 x = - 1

x = - 1/2

4 / ( x - 1 )  = 5 / ( x + 3 )

4 x + 12 = 5 x - 5

4 x - 5 x = - 5 - 12

- x = - 17

x = 17