Ô! Bài này..... hại não quá

a. Xét 2 tam giác DEH và MEH có:

                EH: cạnh chung

           DEH = HEM (EH là phân giác góc E)

               EDH = EMH (=90độ)

=> 2 tam giác DEH = MEH (cạnh huyền-góc nhọn)

b. Bạn có nhớ lộn hk vậy? Sao mà chứng minh đc?

c. Mình cx hk pít làm lun

d. Càng khó đối với mình

=> Mình chỉ làm đc câu a thui!!! Sorry nhìu! 

a.(-b)=a.(-1).b=(-15).(-1)=15

Phải tức chứ! Ỷ làm con giáo viên muốn làm gì thì làm àk

Ôi ôi! Sẽ khó chọn đây! 

Mình đếm là 20 mà! 

I was born in a countryside. I have never gone to big city until I was 12 years old. Last summer, I went to Ho Chi Minh city. It has another named is Sai Gon. I saw Ho Chi Minh city more crowded than countryside. Also it's noisier. I known the diffirent between the big city and the countryside. The most prominent difference are the roads and the buildings. The road in countryside is narrow. Somewhere has potholes too. But in Sai Gon is diffirent. It's larger. There are too many vehicles on the road. But many accidents or traffic jam don't happen. The traffic're very easily. What's about the buildings? The buildings are everywhere and it's very high. Specially, many equipment in big city is very modern. But the air in the big city isn't as fresh as the countryside. Many toxic of exhaust fumes from the factories ỏ public transport make the air become pollution. However, everyone who live in Ho Chi Minh city are kind and friendly. Their life is so comfortable and convinient. They go to work by car. And they look luxurious. I love Sai Gon very much. 

Đó là ý kiến của mình nha!!! ^^

- Lúc đầu vào bạn nên chào hỏi nhé! (hello, good morning, good afternoon, good evening...)

- My name is ..............

- I'm from grade ............. and I'm in class ..............

- Today, I'm .................. years old (mình nghĩ bạn ko cần giới thiệu tuổi)

- I'm live at ............ with ..................

- In addition to learn, I have a lot of hobbies. I like ................... (bạn thích làm việc gì)