svp c'est URGENT a. 5/6 + -1 /3= bon je met l' image mais beaucoup disent que l' image est trop petit ils voyant rien mais faut cliquer sur l' image c'est

a) - 7/50 + 2/25
= - 7/50 + 2 x 2 / 25 x 2
= - 7/50 + 4/50
= - 3/50

b) 1/5 + - 2/3
= 1/5 - 2/3
= 1 x 3 / 5 x 3 - 2 x 5 / 3 x 5
= 3/15 - 10/15
= - 7/15

c) 1/12 - 1/9
= 1 x 3 / 12 x 3 - 1 x 4 / 9 x 4
= 3/36 - 4/36
= - 1/36

d) 4/18 + 5/27
= 4 x 3 / 18 x 3 + 5 x 2 / 27 x 2
= 12/54 + 10/54
= 22/54
= 2 x 11 / 2 x 27
= 11/27

e) 17/- 24 + (- 5/36)
= - 17/24 - 5/36
= - 17 x 3 / 24 x 3 - 5 x 2 / 36 x 2
= - 51/72 - 10/72
= - 61/72

f) 3/16 - - 1/12
= 3/16 + 1/12
= 3 x 3 / 16 x 3 + 1 x 4 / 12 x 4
= 9/48 + 4/48
= 13/48

g) 8/- 17 - (- 1/15)
= - 8/17 + 1/15
= - 8 x 15 / 17 x 15 + 1 x 17 / 15 x 17
= - 120/255 + 17/255
= - 103/255

h) 2/5 + - 2/15 - 7/12
= 2/5 - 2/15 - 7/12
= 2 x 12 / 5 x 12 - 2 x 4 / 15 x 4 - 7 x 5 / 12 x 5
= 24/60 - 8/60 - 35/60
= - 19/60