armchair
aircraft
notebook
bedroom
earphones
cowboy
earthquake
iceberg
keyboard
haircut

Bạn 5 đi rồi mk giải. ok

Ta có abcabc = abc x 1001

Suy ra abcabc là hợp số 

Mà 22 cũng là hợp số 

nên abcabc + 22 là hợp số

1. A(n) ________________ is a sitting place for a passenger in a vehicle next to the window.

2. A(n) ________________ is a sitting place for a passenger in a vehicle next to the passage between the rows of seats.

3. A(n) ________________ is a holiday organized by a travel agent, with arrangements for transport, accommodation, etc... made at an inclusive price.

4. ________________ is luggage weighing more than the limit allowed on an aircraft and likely to an extra charge.

5. A(n) ________________ is a piece of information regarding security given over a public address system, for example loudspeakers.

6. A(n) ________________ is a person who shows the way to others, especially one employed to show tourists around places of interest.

7. A(n) ________________ is a pass for boarding an aircraft, given to passengers when checking in.

8. A(n) ________________ is a person who serves passengers on an aircraft.

Form compound nouns from a word in the upper row and another in the lower, and then fill them in the blanks. Make sure that you use them in the correct form.

1. This is my grandfather’s favorite __________ made in the 19th century.

2. The __________ landed safely at the airport.

3. I use my __________ when I travel on business.

4. My __________ is very small but nice.

5. I asked my nephew to use his __________ because I did not like his music.

6. The __________ loved his horses.

7. The __________ measured 5.3 on the Richter scale.

8. A(n) __________ can sink a ship.

9. __________ is an input device.

10. I need a(n) __________ at every two weeks.

A.magnificent B.delay C.bank D.travel

A. checkout B.erode C.exotic D.decision

A. reasonable B. resort C.season D. excursion

A. safari B.stalagmite C.lag D.package

A.explore B.enviroment C.resort D.expedition

Cho hệ phương trình:

kx+y=7

2x-y=-4

Gọi (x; y) là nghiệm của hệ phương trình . Xác định giá trị của k để P = x 2 + y 2 đạt giá trị nhỏ nhất.

Cho 2 hpt: mx-y=2 và 2x+y=4

a) hệ có 1 nghiệm (x;y)=(1;2)

b)hệ có 1 nghiệm (x;y)=(-3;2)

c) hệ vô nghiệm

d) hệ có nghiệm duy nhất

Cho 2 hpt: 3x+y=1 và x-my=4

a) hệ có 1 nghiệm (x;y)=(1;2)

b)hệ có 1 nghiệm (x;y)=(2;3)

c) hệ vô nghiệm

d) hệ có nghiệm duy nhất