1. That test is shorter than this text.
2. What a hot living room!
3. That toy car is more expensive than this toy car.
4. What a fresh milk!
5. Minh's school is smaller than Nam's school.
6. What an awful weather!
7. What an expensive car!
8. Minh is shorter than Tom.
9. Her test is worst than my test.
10. What an awfulday!
11. That car is cheaper than this car.
12. What fresh apples!
13. Minh's school is smaller than Nam's school.
14. What an awful weather!
15. What a cheap motorbike!
16. Hoa is taller than Nam.
17. What a nice girl!
18. What a terrible weather!
19. What a lovely door!
20. What interesting books!

a: Khi m=1 thì hệ sẽ là x+y=1 và x-y=2

=>x=1,5; y=0,5

b: \(\Leftrightarrow\left\{{}\begin{matrix}x=1-y\\m\left(1-y\right)-y=2m\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=1-y\\m-my-y=2m\end{matrix}\right.\)

=>x=1-y và y(-m-1)=m

=>x=1-y và y=-m/m+1

=>x=1+m/m+1=2m+1/m+1 và y=-m/m+1

Để x,y nguyên thì 2m+1 chia hết cho m+1 và -m chia hết cho m+1

=>\(m+1\in\left\{1;-1\right\}\)

=>\(m\in\left\{0;-2\right\}\)

d

D

C ( chắc vậy )

d

C

B

B