Bài 1 : Tính nhanh
a)35.18-5.7.28
b)24.(16-5)-16.(24-5)
c)29.(19-13)-19.(29-13)
d)31.(-18)+31.(-81)-31
e)(-12).47+(-12).52+(-12)
f) 13.(23+22)-3.(17+28)
G)-48+48.(-78)+48.(-21)
H)135.(171-123)-171.(135-123)
K)-(-2009+97)-74.(-18)+74.(-118)-2009-3
Giúp mình nha , đang cần gấp
Ai nhanh nhất mình tích nha
31.(-18)+31.(-81)-31
= 31.[(-18)+(-81)]
= 31.(-100)
= -3100
135.(171-123)-171.(135-123)
=(135.171-135.123)-(171.135-171.123)
=135.171-135.123-171.135+171.123
=(135.171-171.135)-(135.123-171.123)
=0-123.(135-171)
=0-(-4428)=4428
K)-(-2009+97)-74.(-18)+74.(-118)-2009-3
=2009-97-74.(-18)+74.(-118)-2009-3
=2009-97-74.[(-18)+118]-2009-3
=(2009-2009)-74.100-(97+3)
=0-7400-100
=-7400-100=-7500
Mik bổ sung thêm nha
35.18-5.7.28
= 35.18-35.28
= 35.(28-18)
= 35.10
= 350
24.(16-5)-16.(24-5)
= ( 24-24).(16-16).(5-5)
= 0.0.0
= 0
29.(19-13)-19.(29-13)
= (29-29).(19-19).(13-13)
= 0.0.0
= 0
(-12).47+(-12).52+(-12)
= (-12).(47+52)
= (-12).99
= -1188
13.(23+22)-3.(17+28)
= (13-3).(23+27).(22+28)
= 10.50.50
= 500.50
= 25000
-48+48.(-78)+48.(-21)
= -48.(78+21)
= -48.99
= 4642
2 y cuoi nguoi khac lam nha
