cho mình nghi lại nha mn                                                                                                        \(\dfrac{-3}{5}+\dfrac{28}{5}\cdot\left(\dfrac{43}{56}+\dfrac{5}{24}-\dfrac{21}{63}\right)\)

\(=\dfrac{-3}{5}+\dfrac{28}{5}\cdot\dfrac{9}{14}=\dfrac{-3}{5}+\dfrac{18}{5}=\dfrac{15}{5}=3\)

\(\dfrac{-3}{5}+\dfrac{28}{5}.\left(\dfrac{43}{56}+\dfrac{5}{24}-\dfrac{21}{63}\right)\)

= \(\dfrac{-3}{5}+\dfrac{28}{5}.\dfrac{9}{14}\)

= \(\dfrac{-3}{5}+\dfrac{18}{5}\)

= 3

nếu sai mog bạn thông cảm nhó :>

\(\dfrac{-3}{5}+\dfrac{28}{5}.\left(\dfrac{43}{56}+\dfrac{5}{24}-\dfrac{21}{63}\right)\)

= \(\dfrac{-3}{5}+\dfrac{28}{5}.\dfrac{9}{14}\)

= \(\dfrac{-3}{5}+\dfrac{28.9}{5.14}\)

= \(\dfrac{-3}{5}+\dfrac{18}{5}\)

= \(\dfrac{\left(-3\right)+18}{5}\)

= \(\dfrac{15}{5}=3\)

= 5 x [9/14]

= 45/14

a) 7 x 5 = 35       7 x 6 = 42       7 x 8 = 56       7 x 4 = 28

    35 : 7 = 5       42 : 7 = 6       56 : 7 = 8       28 : 7 = 4

b) 42 : 7 = 6       35 : 7 = 5       63 : 7 = 9       16 : 2 = 8

    14 : 7 = 2       49 : 7 = 7       7 : 7 = 1       48 : 6 = 8

    28 : 7 = 4       70 : =10       21 : 7 = 3       56 : 7 = 8

 7 X 5 = 35

A, 2 x 26 x 5 =( 5 x 2) x 26

10 x 26

=260                   

 b,4 x 37 x 25 =( 4 x 25) x 26

= 100 x 26

= 3700           

 c, 25 x 5 x 4 x 27 x 2 =( 25 x 4 ) x ( 2x 5) x 27

= 100 x 10 x 27 

= 1000x 27 

=27000

d,28 x 64 + 28 x 36 = 28 x ( 64 + 36 )

= 28 x 100

=2800

 e, 769 x 85 - 769 x 75  = 769 x ( 85 - 75 )

=769 x 10

=7690

f, 56 x 37 + 56 x 63 = 56 x ( 37 + 63 )

= 56 x 100

=5600

a. = 26 x (2 x 5)

   = 26 x 10 =260

b.=( 25x4) x37

   =100 x37=3700

c.=(25x4) x(5x2) x27

   =100 x10 x27

   = 27000

d.=28 x( 64+36)

   =28 x100

  = 2800

e.=769 x( 85-75)

    =769 x10 =7690

f. =56 x(37 +63)

  =56 x100

= 5600