bonsoir aider moi en math svp

Bonsoir,

A = 9/6 + 6/9

A = (9 x 3) / (6 x 3) + (6 x 2) / (9 x 2)

A = 27/18 + 12/19

A = 39/18

A = (3 x 13) / (3 x 6)

A = 13/6

B = - 7/4 - 3/10

B = (- 7 x 5) / (4 x 5) - (3 x 2) / (20 x 2)

B = - 35/20 - 6/20

B = - 41/20

C = - 3/8 + 5/16

C = (- 3 x 2) / (8 x 2) + 5/16

C = - 6/16 + 5/16

C = - 1/16

D = 20/4 - 4

D = (4 x 5) / (4 x 1) - 4

D = 5 - 4

D = 1

E = 1/2 - 1/3

E = (1 x 3) / (2 x 3) - (1 x 2) / (3 x 2)

E = 3/6 - 2/6

E = 1/6

F = 25/20 - 7/4

F = 25/20 - (7 x 5) / (4 x 5)

F = 25/20 - 35/20

F = - 10/20

F = (10 x - 1) / (10 x 2)

F = - 1.

Réponse :

A=9/6+6/9= 9x3/6x3 + 6x2/9x2= 27/18+12/18= 39/18

B= -7/4 - 3/10= -7x5/4x5 - 3x2/10x2= -35/20 - 6/20= -41/20

C= -3/8+5/16= -3x2/8x2 +5/16 = -6/16+5/16= -1/16

D=20/4 - 4/1 =20/4 - 4x4/1x4= 20/4 - 16/4= 4/4= 1

E=1/2 - 1/3 = 1x3/2x3 - 1x2/3x2 = 3/6 - 2/6 = 1/6

F=25/20 - 7/4 = 25/20 - 7x5/4x5 = 25/20 - 35/20 = -10/20  

Explications étape par étape