Recopier et compléter par les signes + ; - ou x. a.8/9 .... 2/3 = 2/9 b.7/2 .... -5/4 = -35/8 c.-5/6 .... 9/4 =-15/8 2/5 .... 4/15 = 2/15 aider moi svp cest pou

Bonjour

Recopier et compléter par les signes + ; - ou x.

a.8/9 .... 2/3 = 2/9

= 8/9 + 2/3

= 8/9 + 6/9

= 14/9 donc non

= 8/9 x 2/3

= 16/27 non

= 8/9 - 2/3

= 8/9 - 6/9

= 2/9 oui

b.7/2 .... -5/4 = -35/8

= 7/2 x (-5/4)

= -35/8 oui

c.-5/6 .... 9/4 =-15/8

= -5/6 - 9/4

= -20/24 - 54/24

= -74/24

= -37/12 non

= -5/6 + 9/4

= -20/24 + 54/24

= 24/24

= 1 non

= -5/6 x 9/4

= -45/24

= -(3 x 15)/(3 x 8)

= -15/8 oui

2/5 .... 4/15 = 2/15

= 2/5 + 4/15

= 6/15 + 4/15

= 10/15

= 2/3 non

= 2/5 x 4/15

= 8/75 non

= 2/5 - 4/15

= 6/15 - 4/15

= 2/15 oui