\(\dfrac{2}{67}-\left(\dfrac{3}{7}+\dfrac{2}{67}\right)\\ =\dfrac{2}{67}-\dfrac{215}{469}\\ =\dfrac{-3}{7}\)

\(\dfrac{3}{4}.\dfrac{5}{2}+\dfrac{5}{4}.\dfrac{5}{2}\\ =\left(\dfrac{3}{4}+\dfrac{5}{4}\right).\dfrac{5}{2}\\ =2.\dfrac{5}{2}\\ =\dfrac{5}{1}\)

\(a,\left(37-17\right).\left(-5\right)+23.\left(13-17\right)\)

\(=20.\left(-5\right)+23.\left(-4\right)\)

\(=-100-92\)

\(=-192\)

\(b,\left(-57\right).\left(67-34\right)-67\left(34-57\right)\)

\(=\left(-57\right).33-67.\left(-23\right)\)

\(=-1881+1541\)

\(=-340\)

a) 20.(-5)+23.(-30)

=-100+(-690)

=-790

b)(-57).33-67.(-23)

=-1881-(-1541)

=-340

a, (37-17). (-5) +23 . (-13-17)

=20. (-5) +23. (-30)

= -100-690

= -790

b,(-57) . (67-34)-67.(34-57)

=(-57).33-67 .(-23)

= -1881 + 1541

= -340

a, ( 37 - 17 ) . ( -5 ) + 23 . ( -13 - 17 )                              b, ( -57 ) . ( 67 - 34 ) - 67 . (34 -57 )

= 20 . ( -5 ) + 23 . 4                                                          =-57 . 69 + 57 . 34 - 67 . 34 + 67 . 57 

= -100 + (-690 )                                                               = 57 . 34 - 67 . 34

= -790                                                                            = 34 . ( 57 - 67 )

                                                                                     = 34 . ( -10 )

                                                                                    = -340

nho k cho minh nhieu nha

Cách 1:                                                                                               

a) (37 - 17).(-5) + 23.(-13-17)

=     20.(-5) + 23.(-30)

=     (-100) + (-690)

=           -790

b) (-57).(67 - 34) - 67.(34 - 57)

=       (-57).33 - 67.(-23)

=        1881 -   1541

=             340

Cách 2:

a) (37 - 17).(-5) + 23.(-13 - 17)

=   - 37.5 + 17.5 - 23.13 - 23.17

=   (17.5 - 23.17) - (37.5 + 23.13)

=     17.(5 - 23) - (185 + 299)

=     17.(-18) - 484

=         -306 - 484

=              -790

b) (-57).(67 - 34) - 67.(34 - 57)

= -57.67 + 57.34 - 67.34 + 67.57

= (67.57 - 57.67) + (57.34 - 67.34)

=            34.(57 - 67)

=            34.(-10)

=             -340

Tính:

a) (37 - 17) . (-5) +23 . ( -13 - 17)

=20.18.-30

=-10800

b) (-57) . (67-34) - 67 . (34 - 57)

=(-57).33-67.(-23)

=(-1881)-(-1541)

= -340

a) (37 - 17) . (-5) +23 . ( -13 - 17)

= 20 . (-5) +23 . 4

= 100 + 92

= 192

b) (-57) . (67-34) - 67 . (34 - 57)

= (-57) . 33 -67 . (-23)

= -1881 - (-1541)

= -1881 + 1541

= -340

a là -790

b là -340

a)(37-17).(-5)+23.(-13-17)=-790

b)(-57).(67-34)-67.(34-57)=-340

tk mình nha

a. = 20 x (-5) + 23 x (-30)

    = -100 - 690

    = -790

b. (-57) x 33 - 67 x (-23)

= -1881 + 1541

= -340

a. (37-17)*(-5)+23*(-13 -17)

= 20*(-5)+23*(-30)

= (-100)+-(-690)

=(-790)

b. (-57)*(67-34)-67*(34-57)

=(-57)*33-67*(-23)

=(-1181)-(-1541)

=360

-850

5939

tick cho mk nhá các bn

980

tick mk vài cái lên 200 nha !!!

-850

-340

tick cho mình nha