Répondre :
6a-(3+4a) = 6a-3-4a=2a-3
-7+(3b-8) =-7+3b-8=3b-15
(2-3x) - (4x-7) =-3x+2-4x+7=-7x+9
-4y(2+y)-3(2y-y²) =-8y-4y²-6y+3y²=-y²-14y
-7+(3b-8) =-7+3b-8=3b-15
(2-3x) - (4x-7) =-3x+2-4x+7=-7x+9
-4y(2+y)-3(2y-y²) =-8y-4y²-6y+3y²=-y²-14y