45-58+(-45)+(+58)-3=45-58-45+58-3=(45-45)+(58-58)-3=-3

(-57)-(-12)+3-(-57)=-57+12+3+57=(-57+57)+12+3=15

-(-24)-(-30)+(-24)-30+8=24+30-24-30+8=(24-24)+(30-30)+8=8

-(-12)+(+19)-(+12)+8-19=12+19-12+8-19=(12-12)+(19-19)+8=8

47-(-53)+(-47)-(+53)=47+53-47-53=(47-47)+(53-53)=0

-(+28)+32-(-28)+(-34)=-28+32+28-34=(-28+28)-(34-32)=-2

15-(+72)+(-15)+(+72)=15-72-15+72=(15-15)+(72-72)=0

20-(+46)+(-25)-(-46)=20-46-25+46=(20-25)+(46-46)=-5

28-(-32)+(-28)-32+5=28+32-28-32+5=(28-28)+(32-32)+5=5

-75+(-49)+(+75)+49-12=-75-49+75+49-12=(-75+75)+(49-49)-12=-12

\(...=45-58-45+58-3=-3\)

\(...=-57+12+3+57=15\)

\(...=24+30-24-30+8=8\)

\(...=12+19-12+8-19=8\)

\(...=47+53-47-53=0\)

\(...=-28+32+28-34=-2\)

\(...=15-72-15+72=0\)

\(...=20-46-25+46=-5\)

\(=...28+32-28-32+5=5\)

\(...=-75-49+75+49-12=-12\)

\(\dfrac{19}{28}+\dfrac{23}{47}-\dfrac{15}{8}+\dfrac{9}{28}+\dfrac{24}{47}\)

\(=\left(\dfrac{19}{28}+\dfrac{9}{28}\right)+\left(\dfrac{23}{47}+\dfrac{24}{47}\right)-\dfrac{15}{8}\)

\(=\dfrac{28}{28}+\dfrac{47}{47}-\dfrac{15}{8}\)

\(=1+1-\dfrac{15}{8}\)

\(=\dfrac{1}{8}\)

____________________

\(\dfrac{30}{11}+\dfrac{12}{35}-\dfrac{19}{11}-\dfrac{2}{35}-\dfrac{2}{7}\)

\(=\left(\dfrac{30}{11}-\dfrac{19}{11}\right)+\left(\dfrac{12}{35}-\dfrac{2}{35}\right)-\dfrac{2}{7}\)

\(=\dfrac{11}{11}+\dfrac{10}{35}-\dfrac{2}{7}\)

\(=1+\dfrac{2}{7}-\dfrac{2}{7}\)

\(=1\)

( -12 ).47 + ( - 12 ).52 + ( -12 ) 

= ( -12 ).( 47 + 52 + 1 ) 

= ( -12 ).100

= -1200

13.(23 + 22 ) - 3.( 17 + 28 ) 

= 13.45 - 3.45

= 45.(13 - 3 ) 

= 45.10

=450

(-12).47 + (-12).52 + (-12)

= (-12).47 + (-12).52 + (-12).1

= (-12) . ( 47+52+1)

= (-12) .100

= -1200.

(-12).47+(-12).52+(-12)

=(-12).(47+52+1)

=-1200

13.(23+22)-3.(17+28)

=13.45-3.45

=45.(13-3)

=450

happy new year

\(\begin{array}{*{20}{c}}{ + \begin{array}{*{20}{c}}{47}\\{43}\end{array}}\\\hline{\,\,\,90}\end{array}\)                                     \(\begin{array}{*{20}{c}}{ + \begin{array}{*{20}{c}}{43}\\{47}\end{array}}\\\hline{\,\,\,90}\end{array}\)

\(\begin{array}{*{20}{c}}{ + \begin{array}{*{20}{c}}{65}\\{28}\end{array}}\\\hline{\,\,\,\,93}\end{array}\)                                     \(\begin{array}{*{20}{c}}{ + \begin{array}{*{20}{c}}{28}\\{65}\end{array}}\\\hline{\,\,\,93}\end{array}\)

đáp án lần lượt:90,90,93,93

-56 nhé bn! k cho mình nhé

Mình là người nhanh nhất nè!

ket qua la:-56

45.(28-47) +47.(45-28) = -56

=10.000-47.(72+28)=10.000-47.1000=10.000-470.000=....(tự tính)

47 x{1000+[72+28]}

=47 x {1000 + 100}

=47 x 1100

=51700

-72 . 47 - 28 . 47 = 47 . (-72-28) = 47 . -100 = -4700

-72.|-47|-28.|+47|

= -72.47 - 28.47

= 47. (-72-28)

= 47 . (-100)

= -4700

-72 . |-47| - 28 . |+47|

= -72 . 47 - 28 . 47

= 47 . (-72 - 28)

= 47 . (-100)

= -4700

=5300

đấy bạn

  \(10000-47\cdot72-47\cdot28\)

\(=10000-3384-1316\)

\(=6616-1316\)

\(=5300\)

10000 - 47 x 72 - 47 x 28

= 10000 - (47 x 72 + 47 x 28)

= 10000 - 47 x (72 + 28)

= 10000 - 47 x 100

= 10000 - 4700

= 5300