`3457 - 27 xx 8 - 8 xx 73 + 6543`

`= 3457 + 6543 - 27 xx 8 - 8 xx 73`

`=(3457 + 6543) - (27 xx 8 + 8 xx 73)`

`= 10000 - 8xx (27+73)`

`= 10000 - 8 xx 100`

`= 10000 - 800`

`= 9200`

péo cày gòi đý è

`45/63 = (5xx9)/(7xx9) = 5/7`

=> Chọn `D`

What do you do in your free time?

When do they do to the beach?

How was the homework yesterday?

Who are planting some roses in the garden?

`(7/5 - 1/3) xx 5/11`

`= 16/15 xx 5/11 `

`= 16/33`

was => were

to answer => answer

surf => surfing

heard => hear

you wanted => did you want

understanding => understand

to help => help

was did => did

easily => easy

was helped => helped

Với `x = 3`, ta có: 

`A = 3x^2 - 11 = 3 . 3^2 - 11 = 3 . 9 - 11 = 27 - 11 = 16`

`B = x^3 - 2x = 3^3 - 2 . 3 = 27 - 6 = 21`

Với `x = 1`, ta có: 

`A = 3x^2 - 11 = 3 . 1^2 - 11 = 3 - 11 = -8`

`B = x^3 - 2x = 1^3 - 2 . 1 = 1 - 2 = -1`