Répondre :
Bonsoir;
a) 3a + ( -5 + a) = 3a - 5 + a = 4a - 5
b) 5 - ( -2x + 3 ) = 5 + 2x - 3 = 2x + 2
c) b - 3 - ( 42 + 5 ) = b - 3 - 47 = b - 50
d) 3 - y + ( 6 - 5y ) = 3 - y + 6 - 5y = 9 - 6y
a) 3a + ( -5 + a) = 3a - 5 + a = 4a - 5
b) 5 - ( -2x + 3 ) = 5 + 2x - 3 = 2x + 2
c) b - 3 - ( 42 + 5 ) = b - 3 - 47 = b - 50
d) 3 - y + ( 6 - 5y ) = 3 - y + 6 - 5y = 9 - 6y