71-(-30)-18+(-30)
= 71 + 30 - 18 - 30
= (71-18) + (30-30)
= 53 + 0
= 53
71 - ( -30 ) - 18 + ( -30 )
= 71 + 30 - 18 - 30
= ( 71 + 18 ) + ( 30 - 30 )
= 89 + 0
= 89
71-(-30)-18+(-30)
=71+30-18+(-30)
=[(30+(-30)]+(71-18)
=0+53
=53
71 - ( -30 ) - 18 + ( -30 )
= 71 + 30 - 18 - 30
= 71 - 18 + ( 30 - 30 )
= 71 - 18 + 0
= 53
Xin lỗi nãy mình nhầm .
71 - ( -30 ) - 18 + ( -30 )
= 71 + 30 - 18 - 30
= ( 71 - 18 ) + ( 30 - 30 )
= 53 + 0
= 53
Chúc bạn học tốt!
Ta có: \(71-\left(-30\right)-18+\left(-30\right)\)
\(=71+30-18+\left(-30\right)\)
\(=\left(71-18\right)+\left(30+\left(-30\right)\right)\)
\(=53+0=53\)
71-(-30)-18+(-30)
=71+30-18+(-30)
=71-18+30+(-30)
=53+0
=53
71 - ( - 30 ) - 18 + ( - 30 )
= 71 + 30 - 18 - 30
= 71 - 18 + ( 30 - 30 )
= 71 - 18 + 0
= 53 + 0
= 53