Aidez moi svp a. 6 + 5 xa=3 xa + 17 b. 11 - a= 2 x (a + 1) c.3+4x (a - 1) = 5 xa - 7 pour a=5. pour a = 3. pour a=6.

Réponse:

a)

6+5x × 5 = 3x × 5 +17

6 +25x = 15x +17

25x -15x = 17-6

10x = 11

10x/10 = 11/10

x = 11/10

6+5x × 3 = 3x × 3 +17

6+15x = 9x +17

15-9x = 17 -6

6x = 11

6x/6 = 11/6

x = 11/6

6+5x × 6 = 3x × 6 +17

6+30x = 18x +17

30x -18x = 17-6

12x = 11

12x/12 = 11/12

x = 11/12

b)

11- 5 = 2x(5+1)

6 = 10x + 2

-10x = 2-6

-10x = -4

-10x/-10 = -4/-10

x = 2/5

11- 3= 2x(3+1)

8 = 6x + 2x

8 = 8x

-8x = -8

-8x/-8 = -8/-8

x = 1

11- 6 = 2x(6+1)

5 = 12x + 2x

5 = 14x

-14x = -5

-14x/-14 = -5/-14

x = 5/14

c)

3+4x(5-1) = 5x × 5 -7

3+20x -4x = 25x -7

20x -4x -25x = -7-3

-9x = -10

-9x/-9 = -10/-9

x = 10/9

3+4x(3-1) = 5x × 3 -7

3+12x -4x = 15x -7

12x -4x -15x = -7-3

-7x = -10

-7x/-7 = -10/-7

x = 10/7

3+4x(6-1) = 5x × 6 -7

3+24x -4x = 30x -7

24x -4x -30x = -7-3

-10x = -10

-10x/-10 = -10/-10

x = 1