-1911(1234-1911)

= -1911. (- 677)

= 1293747

-1911( 1234 - 1911)

= -1911 . (-677)

=1293747

Cách 1: \(-1911\left(1234-1911\right)\\ =-1911\cdot\left(-677\right)\\ =1293747\)

Cách 2: \(-1911\left(1234-1911\right)\\ =-1911\cdot1234-\left(-1911\right)\cdot1911\\ =-2358174-\left(-3651921\right)\\ =-2358174+3651921\\ =1293747\)

-1911-(1234-1911)

-1911-1234+1911

(-1911+1911)-1234

0 - 1234

-1234

= -1911-1234+1911

=(-1911+1911)-1234

=0-1234

=-1234

âm 1234 đó

b.-1911-1234+1911=-1911+1911-1234=0-1234=-1234

c.-15.(29+71)=-15.100=-1500

d.156.(72+28)=156.100=15600

a,-1911-(1234-1911)

=>-1911-1234+1911

=>-1234

b,32.(-39)+16.(-22)

=>16.2.(-39)+16.(-22)

=>16.(-78)+16.(-22)

=>16.(-100)

=-1600

li-----------ke nha 

a. -1911-(1234-1911)

=-1911-1234+1911

=(-1911+1911)-1234

=0-1234=-1234

b.32.(-39)+16.(-22)

=16.2.(-39)+16.(-22)

=16.(-78)+16.(-22)

=16.{(-78)+(-22)}

=16.(-100)

=-1600

27.(-3-(-4)=27.1=27

a) 27. ( 13 - 16 ) - 16.( 13 - 27 )

= 27.13 - 27.16 - 16.13 - 16.27

= 27.13 - 16.13

=13.( 27 - 16 )

= 13 . 11

= 143

b) -1911 - ( 1234 - 1911 )

= -1991 + ( -1234 ) + 1911

= -1234

a) 27(13-16) -16(13-27)

= 27.(-3)       -16.(-14)

= (-81)          -(-224)

= -81             + 244

= 143

b) -25.21+25.72+49.25

= -525  + 1800+ 1225

= 1275  + 1225

= 2500

c) -1911-(1234-1911)

= -1991 - (-677)

= -1991 + 677

= -1234

d) -1945-(567-1945)

= -1945 - (-1378)

= -1945 + 1378

= 567

1. -25.72 + 25.21 - 49.25

= 25.(-72) + 25.21 - 49.25

= 25.(-72 + 21 - 49)

= 25. (-100)

= -2500

2. 35(14 - 23) - 23(14 - 35)

= 35. (-9) - 23. (-9)

= -9(35 - 23)

= -9. 12

= -108

3. 8154 -(674 + 8154) + (-98 + 674)

= 8154 - 674 - 8154 + (-98) + 674

= 8154 - 8154 - 674 + 674 + (-98)

= -98

4. 25.21 + 25.72 + 49.25

= 25(21 + 72 + 49)

= 25. 142

= 3550

5. 27(13 - 16) - 16(13 - 27)

= (27.13 - 27.16) - (16.13 - 16.27)

= 27.13 - 27.16 - 16.13 - 16.27

= 27.13 - 16.13 - 27.16 - 16.27

= 27.13 - 16.13

= 13(27 - 16)

= 13.11

= 143

6. -1911 -(1234 - 1911)

= -1911 - 1234 + 1911

= -1911 + 1911 - 1234

= -1234