Bonsoir,
Exercice 1
1) E = 5(x - 3) - 3x + 7
E = 5x - 15 - 3x + 7
E = 2x - 8
2) 5(x - 3) - 3x + 7 = 9
• 5x - 15 - 3x + 7 = 9
• 2x - 8 = 9
• 2x = 9 + 8
• 2x = 17
• x = 17/2 = 8,5
Exercice 2
1) 7(6 - 2x) - 3(4x + 1) = 0
• 42 - 14x - 12x - 3 = 0
• -26x + 39 = 0
• -26x = -39
• x = -39/(-26) = (13 × 3)/(13×2) = 3/2 = 1,5
Bonne soirée !
