Répondre :
(24d-9) (19-40d)
=456d- 960d² - 171 +360d
= -960d² +816d -171
8(6c+9)-(7c+2)(9c+3)
=48c +72 - ( 63c² + 21c + 18c + 6)
= 48c + 72 -63c² -21c -18c -6
= -63c² +9c + 66.
-6(z-9)-(9+4z)
= -6z + 54 - 9 -4z
= - 10z +45
(24d-9) (19-40d)
=456d- 960d² - 171 +360d
= -960d² +816d -171
8(6c+9)-(7c+2)(9c+3)
=48c +72 - ( 63c² + 21c + 18c + 6)
= 48c + 72 -63c² -21c -18c -6
= -63c² +9c + 66.
-6(z-9)-(9+4z)
= -6z + 54 - 9 -4z
= - 10z +45