Bonjours j’ai besoin d’aide pour deuxième exercice

Réponse :

Explications étape par étape

Bonjour

-7/25 x -5/8 = 7/8 x 5/25 = 7/8 x 1/5 = 7/40

18/-49 x 14/27 = -14/49 x 18/27

18/-49 x 14/27 = (-2x7)/(7x7) x (2x9)/(3x9)

18/-49 x 14/27 = -2/7 x 2/3

18/-49 x 14/27 = -4/21

45/28 x 7/-15 = -45/15 x 7/28

45/28 x 7/-15 = (-15x3)/15 x 7/(7x4)

45/28 x 7/-15 = -3 x 1/4

45/28 x 7/-15 = -3/4

-2/6 x (-21/11) = 2/(2 x 3) x 21/11

-2/6 x (-21/11) = 1/3 x 21/11

-2/6 x (-21/11) = 21/3 x 1/11

-2/6 x (-21/11) = (3 x 7)/3 x 1/11

-2/6 x (-21/11) = 7 x 1/11

-2/6 x (-21/11) = 7/11

21/32 x 108/49 = 21/49 x 108/32

21/32 x 108/49 = (3 x 7)/(7 x 7) x (4 x 27)/(4 x 8)

21/32 x 108/49 = 3/7 x 27/8

21/32 x 108/49 = 81/56

-26 x -5/39 = 26/39 x 5

-26 x -5/39 = (2 x 13)/(3 x 13) x 5

-26 x -5/39 = 2/3 x 5

-26 x -5/39 = 10/3

8/5 x -5/21 x (-9/16) = 5/5 x 8/16 x 9/21

8/5 x -5/21 x (-9/16) = 8/(2x8) x (3 x 3)/(3 x 7)

8/5 x -5/21 x (-9/16) = 1/2 x 3/7

8/5 x -5/21 x (-9/16) = 3/14

56/-5 x 30/21 x 7/10 = -56/5 x 30/10 x 7/21

56/-5 x 30/21 x 7/10 = -56/5 x (3 x 10)/10 x 7/(3 x 7)

56/-5 x 30/21 x 7/10 = -56/5 x 3 x 1/3

56/-5 x 30/21 x 7/10 = -56/5

Réponse :

Bonjour

Explications étape par étape

a) -7/25 X -5/8 = +35/200 = 7/40

b) 18/49 X 14/27 = 252/1323 = 28/147

c) 45/28 X 7/-15 = 315/-420 = - 63/84 = - 21/28 = -3/4

e) 21/32 X 108/49 = 2268/1568 = 1134/784 = 567/392

f) -26 X -5/39 = + 130/39

g) 8/5 X -5/21 X (-9/16)

-40/105 X -9/16 = + 360/1680 = 36/168 = 6/28 = 3/14

h) 56/-5 X 30/21 X 7/10

1680/-105 X 7/10 = - 11760/1050 = - 1176/105 = -392/35