Aidez moi svppppoo le 54 svp

Bonsoir

a. 2 / 7 + 4 / 9
= (2 x 9) / (7 x 9) + (4 x 7) / (9 x 7)
= 18 / 63 + 28 / 63
= (18 + 28) / 63
= 46 / 63

b. 3 / 8 - 5 / 3
= (3 x 3) / (8 x 3) - (5 x 8) / (3 x 8)
= 9 / 24 - 40 / 24
= (9 - 40) / 24
= -31 / 24

c. -4 / 5 - 7 / 9
= (-4 x 9) / (5 x 9) - (7 x 5) / (9 x 5)
= -36 / 45 - 35 / 45
= (-36 - 35) / 45
= -71 / 45

d. 1 + 2 / 9
= (1 x 9) / (1 x 9) + 2 / 9
= 9 / 9 + 2 / 9
= (9 + 2) / 9
= 11 / 9

e.  1 - 7 / 3
= (1 x 3) / (1 x 3) - 7 / 3
= 3 / 3 - 7 / 3
= (3 - 7) / 3
= -4 / 3

f. 3 + 3 / 4
= (3 x 4) / (1 x 4) + 3 / 4
= 12 / 4 + 3 / 4
= (12 + 3) / 4
= 15 / 4

Voilà j'espère avoir pu t'aider ^^