214+[120-(214+120)]

=214+120-(214+120)

=214+120-214-120

=(214-214)+(120-120)

=0+0=0

(-321)-[(-321+35)-235]

=(-321)-(-321+35)+235

=(-321)+(-321-35)-235

=-321-(-321) +(235-35)

=0+200

=200

(18+29)+(158-29-18)

=18+29+158-29-18

=(18-18)+(29-29)+158

=0+0+158

=158

(13-135+49)-(13+49)

=13-135+49-13-49

=(13-13)+(49-49)-135

=0-135

= -135

25+(-13+8)

=25+(-5)

=20

7+(-12+43)-[2+(19-34)]

=7+31-[2+(-15)]

=7+31-(-13)

=38+(-13)

=25

nhiều quá, mk phụ chút thôi

1.a)214+[120-(214+120)=214+120-214-120=(214-214)+(120-120)=0+0=0

b)(-321)-[(-321+35)-235]=(-321)+321-35+235=[(-321)+321]+(235-35)=0+200=200

2.a)(18+29)+(158-29-18)=18+29+158-29-18=(18-18)+(29-29)+158=0+0+158=158

ket qua = 379 ban nha

-144-[29-144+149]

=-144-29+144-149

=(-144+144)+(-29-149)

=    0         +     (-178)

=-178

( 18 + 29 ) + ( 158 − 18 − 29 ) = 18 + 29 + 158 − 18 − 29 = ( 18 − 18 ) + ( 29 − 29 ) + 158 = 0 + 0 + 158 = 158.

27 + 514 - 486 + 73 = 128

10 - 12 - 9 - 1 = - 12

Tk mik mik làm nốt cho

Mik mới bị trừ 50 chục điểm bùn qúa T_T

[27 + 514] - [486 - 73]

= 27 + 514 - 486 + 73

= (27 + 73) + ( 514 - 486)

= 100 + 28

= 128

10 - [12 - [-9 -1]]

= 10 - 12 - 9 - 1

= -12

[38 - 29 + 43] - [43 + 38]

= 38 - 29 + 43 - 43 - 38

= (38 - 38) - 29 + (43 - 43)

= 0 - 29 + 0 = -29

\(\text{a) }\left(27+514\right)-\left(486-73\right)\)

\(=27+514-486+73\)

\(=\left(27+73\right)+\left(514-486\right)\)

\(=100+1000\)

\(=1100\)

\(\text{b) }\left(38-29+43\right)-\left(43+28\right)\)

\(=38-29+43-43-28\)

\(=\left(38-28\right)+\left(43-43\right)-29\)

\(=10+0-29\)

\(=10-29\)

\(=-19\)

\(\text{c) }\left(-245-12\right)-\left(18-245\right)\)

\(=-245-12-18+245\)

\(=\left(245-245\right)-\left(12+18\right)\)

\(=0-30\)

\(=-30\)

\(\text{d) }\left(327+414\right)-\left(-586-73\right)\)

\(=327+414+586+73\)

\(=\left(327+73\right)+\left(414+586\right)\)

\(=400+1000\)

\(=1400\)

a)  (27+514)-(486-73)

= 27 + 514 - 486 + 73

= ( 27+ 73 ) + ( 514 - 486 )

= 100 + 1000

= 1100
 

mk ko biết

- (-15) – (-3 +15 – 8)

= 15 + 3 - 15 + 8 

= 11

 b) + ( - 143 + 17 – 35) – ( -143 + 37 – 35)

= -143 + 17 - 35 + 143 - 37 + 35 

= -20 

c) 50 - ( 47 + 50 - 18 ) -  ( 47 + 18 )

= 50 - 47 - 50 + 18 - 47 - 18 

= -47 - 47 

= -94 

d) 16 - ( -15 ) + ( -20 ) - | -24 | 

= 16 + 15 - 20 - 24 

= -13 

a, -(-15) - ( -3 + 15 - 8 ) = 15 - 3 + 15 + 8

                                      = 12 + 15 + 8

                                      = 27 + 8 

                                       = 35

b, + ( -143 + 17 - 35 ) - ( -143 + 37 - 35 )

=  -143 + 17 - 35 + 143 - 37 + 35

=  ( -143 + 143 ) + [ 17 + (-37 )] + ( -35 + 35)

=  0 + 20 + 0

= 20

c, 50 - ( 47 + 50 -18 ) - ( +47 + 18 )

= 50 - 47 - 50 + 18 - (-47) - 18

= ( 50 - 50 ) - [ 47 - (-47)] + (18 - 18 )

= 0 - 0 + 0

= 0

d, 16 - (-15) + (-20) -I -24 I

=  16 + 15 - 20 + 24

= 30 - 20 + 24

= 10 + 24

= 34 

[144 - 97] - 144

= 144 - 97 - 144

= 0 - 97

= -97

[-145] - [18 - 145]

= 145 - 18 + 145

= 0 - 18

= -18

111 + [-11 + 27]

= 111 - 11 + 27

= 100 + 27

= 127

(144-97)-144=144-97-144= -97

(-145)-(18-145)=(-145)-18+145=-18

111+(-11+27)=111-11+27=127

   ( 18 + 29) + ( 158 - 18 - 29)

=  18 + 29 + 158 - 18 - 29

= ( 18 - 18) + ( 29  - 29) + 158

= 0 + 0 + 158

= 158 

    [ 18 + 29 ] + [ 158 - 18 - 29 ]

=       47        +         111

=   158

158