mình đag cần gấp 

(5/6-13/19) - (17/30-13/19)

=(13/19-13/19)-(5/6-17/30)

=0-4/15

=4/15

77-0.23 =

77.(-13)-13.23

Sử dụng t/c giao hoán,ta có

=13.(-77)-13.23

=-[13.(77-23)

=-(13.54)

=-702

hình như đề bài của bạn phải như này: 77.(-13)+13.23 mới đúng

 k nha

\(\left(-51+\left|13\right|\right)-\left(13-\left|-51\right|-2018\right)\)

\(=\left(-51+13\right)-\left(13-51-2018\right)\)

\(=-38-\left(-2056\right)\)

\(=2018\)

=_51+13_13+51+2018

=(_51+51)+(13_13)+2018

=0+0+2018

2018

(_ la dau tru)

hoi co y

( − 4 ) .13. ( − 250 ) = ( − 4 ) . ( − 250 ) .13 = 1000.13 = 13000

Sửa đề: \(\frac59\cdot\frac{7}{13}-\frac{30}{23}+\frac69\cdot\frac{5}{13}-\frac{7}{13}\)

\(=\frac{7}{13}\left(\frac59-1\right)-\frac{30}{23}+\frac{30}{117}=\frac{7}{13}\cdot\frac{-4}{9}-\frac{30}{23}+\frac{30}{117}\)

\(=\frac{-52}{117}+\frac{30}{117}-\frac{30}{23}\)

\(=\frac{-22}{117}-\frac{30}{23}=\frac{-22\cdot23-30\cdot117}{23\cdot117}=\frac{-4016}{2691}\)

( 43 − 13 ) . ( − 3 ) + 27. ( − 14 − 16 ) = 30. ( − 3 ) + 27. ( − 30 ) = ( − 30 ) .3 + 27. ( − 30 ) = ( − 30 ) . ( 3 + 27 ) = ( − 30 ) .30 = − 90