Cho tam giác ABC vuông tại A, biết AB=1/3AC.

a)Tính số đo B và C của tam giác ABC.

b) Kẻ AH vuông góc BC. Tính tỉ số BH/CH.

c) Biết diện tích tam giác ABC bằng 15cm^2. Tính diện tích tam giác ABH

GIÚP MIK VS

cho tam giác ABC vuông tại A , đường cao AH. Độ dài BH = 4cm , CH =16 cm. độ dài đoạn AB

Ex1. COMPLETE THE SENTENCES

1. He told / me that / he / interest / play games / his free time

2. We / feel very bore ytd / because / our friends / not come / my house

3. I / remember / tell you / this before

4. His house / big / than my house

5. I / rather you / do this work / slow 

6. Because / his ill last week / he / not go / fish / us / the weekend

7. His family / arrive / HN / when he / boy

8. It / such bore film / noone / enjoy / watch

9. The water / too / dirt / we / drink now

10. He / very fame / his novels

j

Ex1 COMPLETE THE SENTENCCES

    1. He / be able / do this work every /good

    2. We / want / half an hour / reach the water           fall  ytd

    3. If you / want / pass the exam /  you must /           study hard

   4. They / planned / have a trip / the vilage / june

   5. Nam / the same / old / us 

   6. What / people / often do / a living 

   7. His village / be / the North / the city 

   8. They said / us that / they / not often / spend        time /  play games

   9. He said that he / very pride / his father 

   10. Coffee / drink / me last night