Question

tính nhanh : 

- 75. (55 - 14) - 55.(14 - 75)

Answer 1

=280 nhớ kick nhé

Answer 2

= -75 . 55 + 75 . 14 - 55 . 14 + 55 . 75

= ( -75 . 55 + 55 . 75 ) + ( 75 . 14 - 55 . 14 )

= 0 + 14 . ( 75 - 55 ) 

= 0 + 14 . 20 

= 0 + 280

= 280

Answer 3

- 75 x 55 - 14 x ( - 75 ) - 55 x 14 + 55 x 75

= ( - 75 x 55 + 55 - 75 ) - ( 14 x 75 + 14 x 55 )

= 0 - 1820 = - 1820

Answer 4

= - 75 . 55 + 75 . 14 -55 . 14 + 55 . 75

=( -75 . 55 + 55 . 75) + (75 . 14 - 55 .14)

= 0 + 14 . (75 - 55)

= 0 + 14 . 20

= 0 + 280

= 280