Bonjour
5 + 4x = 9x
5 + 4 * 10 = 9 * 10
5 + 40 = 90
45 ≠ 90
3 * (2x + 5) = 6x + 5
3 * (2 * 10 + 5) = 6 * 10 + 5
3 * (20 + 5) = 60 + 5
60 + 15 = 65
75 ≠ 65
2x² = 4x
2 * 10² = 4 * 10
2 * 100 = 40
200 ≠ 40
x² = - 100
10² = - 100
100 ≠ - 100
3 * (2x + 5) = 10x - 25
3 * (2 * 10 + 5) = 10 * 10 - 25
3 * (20 + 5) = 100 - 25
60 + 15 = 75
75 = 75 → Vraie
5 + 4x = 9x - 45
5 + 4 * 10 = 9 * 10 - 45
5 + 20 = 90 - 45
25 ≠ 45
x² - 100 = 0
10² - 100 = 0
100 - 100 = 0
0 = 0 → Vraie
3 * (2x + 5) = 6x + 15
3 * (2 * 10 + 5) = 6 * 10 + 15
3 * (20 + 5) = 60 + 15
3 * 25 = 75
75 = 75 → Vraie.
