Réponse :
49) calculer les expressions suivantes
A = 7/3 - 4/3 + 8/5
= 35/15 - 20/15 + 24/15
= 59/15 - 20/15
= 39/15
= 13/5
B = - 4/9 x 1/5 ÷ 3/7 = - 4/45/3/7 = - 28/135
C = - 8/3 + - 5/6 + 7/4
= - 32/12 - 10/12 + 21/12
= - 42/12 + 21/12
= - 21/12
= - 7/4
50 calculer les expressions suivantes
L = - 7/5 ÷ (2/9 - 7/18)
= - 7/5 ÷ (4/18 - 7/18)
= - 7/5 ÷ (- 3/18)
= 42/5
M = (4/5 + - 3/2) ÷ (- 9/4 - 1/6)
= (8/10 - 15/10) ÷ (- 27/12 - 2/12)
= - 7/10 ÷ (- 29/12)
= 42/145
Explications étape par étape :
