Répondre :
7-2x(-10-8/4)=7-2x(-10-2)=7-2x(-12)=7-(-24)=7+24=31
(3-5(3-9))x(-2)=(3-5(-6))x(-2)=3-(-30)x(-2)=33x(-2)=-66
(3-5(3-9))x(-2)=(3-5(-6))x(-2)=3-(-30)x(-2)=33x(-2)=-66