Bonsoir
3/9 + 5/2
= (3 x 2)/(9 x 2) + (5 x 9)/(2 x 9)
= 6/18 + 45/18
= 51/18
6/7 - 2/3
= (6 x 3)/(7 x 3) - (2 x 7)/(3 x 7)
= 18/21 - 14/18
= 4/21
7/4 - 9/5
= (7 x 5)/(4 x 5) - (9 x 4)/(5 x 4)
= 35/20 - 36/20
= -1/20
3/8 + 1/7
= (3 x 7)/(8 x 7) + (1 x 8)/(7 x 8)
= 21/56 + 8/56
= 29/56
-7/3 + (-1/4)
= (-7 x 4)/(3 x 4) - (1 x 3)/(4 x 3)
= -28/12 - 3/12
= -31/12
2/11 - 3/10
= (2 x 10)/(11 x 10) - (3 x 11)/(10 x 11)
= 20/110 - 33/110
= -13/110
