aider moi svp ses urgenttt ses l'exos 2 et 3

Exercice 2

A = 2 * (x + 7)
A = 2x + 14

B = 2 (x + 7) + 3 (x - 4)
B = 2x + 14 + 3x - 12
B = 2x + 3x + 14 - 12
B = 5x + 2

C = 3x (x + 4)
C = 3x² + 12x

Exercice 3

D = 21/5 - 6/5
D = 15/5
D = 5 x 3 / 5 x 1
D = 3

E = 3 - 5/6 + 7/3
E = 3 x 6 / 1 x 6 - 5/6 + 7 x 2 / 3 x 2
E = 18/6 - 5/6 + 14/6
E = 27/6
E = 3 x 9 / 3 x 2
E = 9/2

F = 5/2 + (7/24 + 5/3 - 3/4)
F = 5 x 12 / 2 x 12 + (7/24 + 5 x 8 / 3 x 8 - 3 x 6 / 4 x 6)
F = 60/24 - (7/24 + 40/24 - 18/24)
F = 60/24 - 29/24
F = 31/24