resoudre avec les fraction 1. -1/2x+3=x-7 2. 3/2x+4=2x-5 3. 3x+5=-7/9 4. 7x-1/4=5/11 5. x-1/4-5=2x-3/2+3/4 6. 2x/7-6/5=9/10 7. x/3+9/4=-5x/6+15/2 8. 2x+3/6-x-1/

Bonsoir,

1. -1/2x+3=x-7
0,5x - x = - 7 - 3
- 0,5x = - 10
x = 10/0,5
x = 20

2. 3/2x+4=2x-5
1,5x - 2x = - 5 - 4
- 0,5x = - 9
x = 9/0,5
x = 18

3. 3x+5=-7/9
27/9x + 45/9 = - 7/9
27x = - 7 - 45
27x = - 52
x = - 52/27

4. 7x-1/4=5/11
7x = 5/11 + 1/4
308/44x = 20/44 + 11/44
308x = 20 + 11
308x = 31
x = 31/308

5. x-1/4-5=2x-3/2+3/4
4/4x - 8/4x = - 6/4 + 3/4 - 1/4 - 20/4
4x - 8x = - 27 + 3
- 4x = - 24
x = 24/4
x = 6

6. 2x/7-6/5=9/10
20/70x - 84/70 = 63/70
20x = 63 + 87
20x = 150
x = 150/20
x = 7,5

7. x/3+9/4=-5x/6+15/2
8/24x + 54/24 = - 20/24x + 180/24
8x + 20x = 180 - 54
28x = 126
x = 126/28
x = 4,5

8. 2x+3/6-x-1/6=x+2/3+2
12/6x + 3/6 - 6/6x - 1/6 = 6/6x + 4/6 + 12/6
12x - 6x - 6x = 4 + 12 - 3 + 1
0x = impossible

9. 3-2x/5-x-2/10=5x+2/2-1/5
30/10 - 4/10x - 10/10x - 2/10 = 50/10x + 10/10 - 2/10
- 4x - 10x - 50x = 10 - 2 - 30 + 2
- 64x = 20
x = - 20/64
x = - 0,3125

10. 2x+3/2=7x-2/3
12/6x + 9/6 = 42/6x- 4/6
12x - 42x = - 4 - 9
- 30x = - 13
x = 13/30