Sagot :
Réponse:
A=. 7/5 -4/5*1/3
7/5- 4/15
21/15- 4/15
=17/15
B= (2/3- 7/5)/7
(10/15- 21/15)/7
(-11/15)/7
-77/15
Explications étape par étape:
A=7/5-4/5×1/3
A=7/5-4×1/5×3
A=7/5-4/15
A=7×3/5×3-4/15
A=21/15-4/15
A=17/15
B=(2/3-7/5)÷7
B=(2×5/3×5-7×3/3×5)÷7
B=(10/15-21/15)÷7
B= -11/15÷7
B=-11/15×1/7
B= -11×1/15×7
B= -11/105