svp j'ai besoin d'aide pour mes exerice de maths merci en avance .

Bonjour

A = 5/4 + 10/4 x 9/8

A = 5/4 + (2 x 5 x 9)/(4 x 2 x 4)

A = (5 x 4)/(4 x 4) + (5 x 9)/(4 x 4)

A = 20/16 + 45/16

A = 65/16

B = (2/3 + 1/5) : (11/4 - 3/5)

B = [(2 x 5)/(3 x 5) + (1 x 3)/(5 x 3)] : [(11 x 5)/(4 x 5) - (3 x 4)/(5 x 4)]
B = (10/15 + 3/15) : (55/20 - 12/20)

B = 13/15 : (43/20)

B = 13/15 x 20/43

B = (13 x 20)/(15 x 43)

B = (13 x 5 x 4)/(5 x 3 x 43)

B = (13 x 4)/(3 x 43)

B = 52/129

C = (-8 - 2 x 3)/(7 - 11)

C = (-8 - 6)/(-4)

C = -14/(-4)

C = (2 x 7)/(2 x 2)

C = 7/2