Sagot :

Réponse:

A) 1/2 + 7/5= 1×5/2×5 + 7×2/5×2= 5/10 + 14/10= 19/10

B) 8/7 - 7/12= 8×12/7×12 - 7×7/12×7= 96/84 - 49/84= 47/84

C)2/23 - 11/10= 2×10/23×10 - 11×23/10×23= 20/230 - 253/230=-233/230

D) -3/4 - 7/9= -3×9/4×9 - 7×4/4×9= -27/36 - 28/36=-55/36