7 sur 5 -(-9 sur 5) =? 8sur24+(-7 sur 3)=? 4 sur 7 -(-2) sur 3=? Merci d avance

Bonsoir,

7/5 - (- 9/5)

= 7/5 + 9/5

= 16/5

8/24 + (- 7/3)

= 8/24 - 7/3

= 8/24 - (7 x 8) / (3 x 8)

= 8/24 - 56/24

= - 48/24

= (24 x - 2) / (24 x 1)

= - 2

4/7 - (- 2)/3

= 4/7 + 2/3

= (4 x 3) / (7 x 3) + (2 x 7) / (3 x 7)

= 12/24 + 14/24

= 26/24

= (2 x 13) / (2 x 12)

= 13/12.

Bonjour,

1) 7/5 - -9/5

= 7/5+9/5

= 7+9/5

= 16/5

2) 8/24 + -7/3

= 8/24 + -56/24

= 8/24 - 56/24

= -48/24 = -2

3) 4/7 - -2/3

= 4/7 + 2/3

= 12/24 + 14/24

= 26/24 = 13/12

Voilà :)