bonjour donner les résultats sous forme d'une fraction irréductible: 1/5 - -11/25 + 21/100= -2/-5 x -10/6 x -9/7= -6/7 x 14/24 + 3/-2= merci davance

Bonjour,

1/5 - -11/25 + 21/100

= 1/5 + 11/25 + 21/100

= (1 x 20) / (5 x 20) + (11 x 4) / (25 x 4) + 21/100

= 20/100 + 44/100 + 21/100

= 85/100

= (5 x 17) / (5 x 20)

= 17/20

-2/-5 x -10/6 x -9/7

= 2/5 x - 10/6 x - 9/7

= - 20/30 x - 9/7

= 180/210

= (30 x 6) / (30 x 7)

= 6/7

-6/7 x 14/24 + 3/-2

= - 84/168 - 3/2

= (84 x - 1) / (84 x 2) - 3/2

= - 1/2 - 3/2

= - 4/2

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

= - 2.