ko hiểu

Bài làm

1) 29( 85 - 47 ) + 85( 47 - 29 )

= 29 . 85 - 29 . 47 + 85 . 47 - 29 . 85

= 29 . 85 . ( -29 . 47 + 85 . 47 )

= 29 . 85 . [ 47( -29 + 82 ) ]

= 29 . 85 . ( 47 . 53 )

= 6140315

2) 3 - | x - 7 | = -12

=> | x - 7 | = 3 - ( -12 )

=> | x - 7 | = 15 

=> \(\orbr{\begin{cases}x-7=15\\x-7=-15\end{cases}\Rightarrow\orbr{\begin{cases}x=22\\x=-8\end{cases}}}\)

Vậy x = { 22; -8 } 

Trả lời :

Câu 1.

29 . (85 - 47) + 85 . (47 - 29)

= 29 . 85 - 29 . 47 + 85 . 47 - 85 . 29

= (29 . 85 - 85 . 29) + (85 . 47 - 29 . 47)

= 0 + 2632 

= 2632

Câu 2.

3 - |x - 7| = - 12

=> |x - 7| = 3 - (- 12)

=> |x - 7| = 3 + 12

=> |x - 7| = 15

=> x - 7 = \(\pm15\)

\(\Rightarrow\orbr{\begin{cases}x-7=15\\x-7=-15\end{cases}\Rightarrow\orbr{\begin{cases}x=22\\x=-8\end{cases}}}\)

Đ/s : 0

k cho t đi hà crazy

nguyen vt ha la con cho cua cong san

29(85 - 47) + 85(47 - 29)

= 29.85 - 29.47 + 85.47 - 85.29

= (29.85 - 85.29) - (29 . 47 - 85.47)

= - 47.(29 - 85)

= -47.(-56 ) = 2632

29( 85 - 47 ) + 85( 47 - 29 )

= 29 . 85 - 29 . 47 + 85 . 47 - 85 .29

= -29 . 47 + 85 . 47

= 47(- 29 + 85 )

= 47 . 56 = 3136

\(29(85-47)+85(47-29)\)

\(=29\cdot85-29\cdot47+85\cdot47-85\cdot29\)

\(=(29\cdot85-85\cdot29)-(29\cdot47-85\cdot47)\)

\(=0-\left[29-85\right]\cdot47=0-(-2536)=2536\)

  (-29).(85-47)-85.(47-29)

=(-29).38-85.18

=-1102-1530

=-2632

cam on ban nh a :>

a/-2632

b/-232

c/16

a)-2632

b)23500

(-29).(85-47)-85.(47-29)

=(-29).85+29.47-85.47+85.29

=85.[(-29)+29]+47.(29-85)

=85.0+47.(-56)

=0+(-2632)

(-167) . (67-34) - 67 . ( 34- 167)

=-167.67+167.34 - 67.34+67.167

=167.34-67.34

=34.(167-67)

=34.100=3400

lm cả cách nha

a) 29.(85-47)+85.(47-29)= 29.85-29.47+85.47-85.29
                                   =(29.85-85.29) -29.47+85.47
                                   =0-29.47+85.47
                                   = -29.47+85.47
                                   = (-29+85).47
                                   =56.47
                                   = 2632     
b)47.(23+50)-23.(47+50)= 47.23+47.50-23.47+23.50
                                  =(47.23-23.47)+47.50+23.50
                                  =0+47.50+23.50
                                  =47.50+23.50       
                                  =(47+23).50
                                  =70.50
                                  =3500
tích ^.^ ~

a) 29.(85-47)+85(47-29)

=29.38+85.18

=1102+1520

=2622

b)47.(23+50)-23.(47+50)

=47.73-23.97

=3431-2231

=1200

k mình nha...^_^...kb nữa... thanks

-29.(85-47) - 85.(47-29)

= -29.85 + 29.47 - 85.47 + 85.29

= ( -29.85 + 85.29) + 29.47-85.47

= 0 + 47.(29-85)

= 47.(-56)

= -2632

- 29 . ( 85 - 47 )  -  85 . ( 47 - 29 )

= - 29 . 85 + 29 . 47 - 85 . 47 + 85 . 29

= ( - 29 . 85 + 85 . 29 ) + 29 . 47 - 85 . 47

= 0 + 47 . ( 29 - 85 )

= 47 . ( - 56 )

= - 2632