Bonjour
- 5/3 - 11/6
= (- 5 x 2) / (3 x 2) - 11/6
= - 10/6 - 11/6
= - 21/6
= (2 x - 7) / (2 x 3)
= - 7/3
- 13/9 - - 7/3
= - 13/9 + 7/3
= - 13/9 + (7 x 3) / (3 x 3)
= - 13/9 + 21/9
= 8/9
13/5 - 5/3
= (13 x 3) / (5 x 3) - (5 x 5) / (3 x 5)
= 39/15 - 25/15
= 14/15
- 7/20 + - 2/6
= (- 7 x 3) / (20 x 3) - (2 x 10) / (6 x 10)
= - 21/60 - 20/60
= - 41/60
- 5/20 - 9/- 6
= (- 5 x 3) / (20 x 3) + (9 x 10) / (6 x 10)
= - 15/60 + 90/60
= 75/60
= (15 x 5) / (15 x 4)
= 5/4
- 3 - 3/5
= (- 3 x 5) / (1 x 5) - 3/5
= - 15/5 - 3/5
= - 18/5.
