Réponse :
Explications étape par étape
Bonjour,
Calculer sans calculatrice et de deux façons différentes les expressions suivantes:
a.4x(7+5)
= 4 x 7 + 4 x 5
= 28 + 20
= 48
= 4 x 12
= 48
b.4x3+5x3
= 12 + 15
= 27
= 3 x (4 + 5)
= 3 x 9
= 27
c.(8+5)x2
= 2 x 8 + 2 x 5
= 16 + 10
= 26
= 13 x 2
= 26
d.10x7-7x2
= 70 - 14
= 56
= 7 x (10 - 2)
= 7 x 8
= 56
e.5x(8-2)
= 5 x 8 - 5 x 2
= 40 - 10
= 30
= 5 x 6
= 30
f.34x20-14x20
= 680 - 280
= 400
= 20 x (34 - 14)
= 20 x 20
= 400
