Verified answer

Hello,

3

3 * 2 = 6

6 + 4 = 10

3 * 10 = 30

30 - (6 * 3) = 30 - 18 = 12

10

10 * 2 = 20

20 + 4 = 24

24 * 3 = 72

72 - (10 * 6) = 72 - 60 = 12

5

5 * 2 = 10

10 + 4 = 14

14 * 3 = 42

42 - (6 * 5) = 42 - 30 = 12

On obtient toujours 12

Prouvons le :

x

2x

2x + 4

3(2x + 4) = 6x + 12

6x + 12 - 6x = 12

C'est vérifié.