je n'y arrive pas 8(y-3)= 6(3y+9)= 3y(2y-7)= 4(2y+5)+3(y-6)= 2(a+7(a+3b))=

bonjour

8 y - 24

18 y + 54

6 y² - 21 y

8 y + 5 + 3 y - 18 = 11 y - 13

2 ( a + 7 a + 21 b) = 2 a + 14 a + 42 b = 16 a + 42 b

8×y-3×8=24-8y=16y
6×3y+6×9=18y+54=132
3y×2y+7×3y=6y+21y=27y au carre
4×2y+5×4=8y+20=28y+3×y-3×6=3y-18=15+28y=43y
2×a+2×7=2a+17=19a+2×a+3b=2a+3b=5ab+19a =24a au carre b