`3/7+2/5+4/7`

`=(3/7+4/7)+2/5`

`=1+2/5`

`=5/5+2/5`

`=7/5`

`20/34+4/9+7/17`

`=(20/34+7/17)+4/9`

`=(20/34+14/34)+4/9`

`=34/34+4/9`

`=1+4/9`

`=9/9+4/9`

`=13/9`

`48xx2+96+48xx6`

`=48xx2+48xx2+48xx6`

`=48xx(2+2+6)`

`=48xx10`

`=480`

câu thứ hai thì làm như này em nhé:

    \(\dfrac{20}{34}\) + \(\dfrac{4}{9}\) + \(\dfrac{7}{17}\)

= (\(\dfrac{20}{34}\) + \(\dfrac{7}{17}\)) + \(\dfrac{4}{9}\)

=  (\(\dfrac{10}{17}\) + \(\dfrac{7}{17}\)) + \(\dfrac{4}{9}\)

= 1 + \(\dfrac{4}{9}\)

= \(\dfrac{13}{9}\)

a: \(17464-17464:74-74\cdot158\)

\(=17464\cdot\left(1-\dfrac{1}{74}\right)-74\cdot158\)

\(=17464\cdot\dfrac{73}{74}-74\cdot158\)

\(=5536\)

5536 nhé bạn

thấy đúng thì tim nhé

=5536

a) ( -48 ) + 48 . ( -78 ) + 48 . ( -24 )

=      48 . ( -1 - 78 - 24 )

=      48 .     ( -103 )

=           -4944

b) 31 . ( -18 ) + 31 . ( -81 ) - 31

=      31 . ( -18 - 81 - 1 )

=      31 .        62

=         -3100

c) 35 x 18 - 5 x 7 x 28 

 =   35 x 18 - 35 x 28

=      35 x ( 18 - 28 )

=      35 x   ( -10 )

=            -350

d) ( -16 ) + 24 + 16 - 34

=  [ ( -16 ) + 16 ] + ( 24 - 34 ) 

=          0           +      ( - 10 )

=                  -10

giải giúp mình với 

17464 - 17464 : 74 - 74 x 158

= 158 x ( 17464 - 17464 ) : ( 74 - 74 )

= 158 x 0 : 0

= 0 x 0

= 0

\(37\times46+37\times51+111\)

\(=37\times46+37\times51+37\times3\)

\(=37\times\left(46+51+3\right)\)

\(=37\times100\)

\(=3700\)

------------

\(172\times47+86\times8-34\times4\)

\(=172\times47+172\times4-34\times4\)

\(=172\times\left(47+4\right)-34\times4\)

\(=172\times51-34\times4\)

\(=172\times3\times17-17\times2\times4\)

\(=17\times\left(172\times3-2\times4\right)\)

\(=17\times\left(516-8\right)\)

\(=17\times508\)

\(=8636\)

------------

\(35\times215-35\times200-175\)

\(=35\times215-35\times200-35\times5\)

\(=35\times\left(215-200-5\right)\)

\(=35\times10\)

\(=350\)

------------

\(48\times56+28\times104\)

\(=48\times2\times28+28\times104\)

\(=28\times\left(48\times2+104\right)\)

\(=28\times200\)

\(=5600\)

88 800

261 304

không phải nhé

a. 34^2 + 66^2 + 68 x 66

= 34 x 34 + 66 x 66 + 68 x 66

= 34 x 34 + 66 x (66 + 68)

= 34 x 34 + 66 x 134

= 34 x 34 + 66 x 34 + 66 x 100

= 34 x (34 + 66) + 66 x 100

= 34 x 100 + 66 x 100

= (34 + 66) x 100

= 100 x 100

= 10000

\(34^2+66^2+68.66\)

\(=34.34+66.66+68.66\)

\(=34.34+66.\left(68+66\right)\)

\(=34.34+66.134\)

\(=34.34+66.\left(100+34\right)\)

\(=34.34+66.100+66.34\)

\(=34.\left(66+34\right)+66.100\)

\(=34.100+66.100\)

\(=\left(34+66\right).100\)

\(=100^2\)

\(=10000\)

a,x+7=19-1

 x+7=18

 x     =18-7

 x     =11.

b,x+6=48-19

x+6   =29

x       =29-6

x       =23.

c,x+34=23+22

x+34   =45

x         =45-34

x         =11.

d,x+23=86-15

x+23   =71

x         =71-23

x         =48.

y+7=19-1

y+7=18

y=18-7

y=11

x+6=48-19

x+6=29

x=29-6

x=23

y+34=23+22

y+34=55

y=55-34

y=21

x+23=86-15

x+23=71

x=71-23

x=48

bạn ơi k cho mình với

A= 5563

B= 11859

C=0

D =167802

         học tốt

kb rùi đấy bạn đồng ý đi