Verified answer

Bonjour,

A = 5 (a + 2) - (6a - 7)

A = 5a + 10 - 6a + 7

A = 5a - 6a + 10 + 7

A = - a + 17

B = - b (3b + 7) + (5 - b) * b

B = - 3b² - 7b + 5b - b²

B = - 3b² - b² - 7b + 5b

B = - 4b² - 2b

C = - c (4 + 3c) - (9 - 2c + 6c²)

C = - 4c - 3c² - 9 + 2c - 6c²

C = - 3c² - 6c² - 4c + 2c - 9

C = - 9c² - 2c - 9

D = - 5d + 5d (d - 2) - 6 (7 - 3d)

D = - 5d + 5d² - 10d - 42 + 18d

D = 5d² - 5d - 10d + 18d - 42

D = 5d² + 3d - 42.

Réponse :

bonjour

Explications étape par étape

A=5(a+2)-(6a-7)

5a+10-6a+7

-a+17

B=-b(3b+7)+(5-b)*b

-3b²-7b+5b-b²

-4b²-2b

C=-c(4+3c)-(9-2c+6c²)

-4c-3c²-9+2c-6c²

-9c²-2c-9

D=-5d+5d(d-2)-6(7-3d)

-5d+5d²-10d-42+18d

5d²+3d-42