15. She runs every day, so she is very fit. A. Simple B. Compound C. Complex D. Compound-complex 16. Because she runs every day, she is very fit. A. Simple B. Compound C. Complex D. Compound-complex 17. The new girl in our class has a brother in grade 7 and a sister in grade 9. A. Simple B. Compound C. Complex D. Compound-complex 18. You should read every day if you want to improve your English more quickly. A. Simple B. Compound C. Complex D. Compound-complex 19. Although it was cold and the rain was getting heavier, we decided to go fishing as planned. A. Simple B. Compound C. Complex D. Compound-complex 20. You should start working a little harder or you are going to fail your test. A. Simple B. Compound C. Complex D. Compound-complex 21. I didn't know what time it was so I was very late to class. A. Simple B. Compound C. Complex D. Compound-complex 22. Most European countries now use the Euro, but the United Kingdom still uses the pound (£). A. Simple B. Compound C. Complex D. Compound-complex 23. To build a doll's house you need wood, a hammer, a saw, and lots of nails. A. Simple B. Compound C. Complex D. Compound-complex 24. She failed her driving test because she didn't look in her mirror often enough. A. Simple B. Compound C. Complex D. Compound-complex 25. He got up, walked over to the window, and jumped out.A. Simple B. Compound C. Complex D. Compound-complex 26. We met rather few people who spoke English. A. Simple B. Compound C. Complex D. Compound-complex 27. He will never leave home because he hasn't got the courage to. A. Simple B. Compound C. Complex D. Compound-complex 28.  I have got four sisters and each of them is quite different from the others. A. Simple B. Compound C. Complex D. Compound-complex 29. Two minutes ago the child was fast asleep, but now he is wide awake. A. Simple B. Compound C. Complex D. Compound-complex 30. I guess she just doesn't respect you. A. Simple B. Compound C. Complex D. Compound-complex

- Xét ΔADC và ΔDBC, ta có :

DC cạnh chung

AD = DB ( gt )

AC = CB ( gt )

=> Δ ADC = ΔDBC ( c-c-c )

=> CD tia phân giác góc ACB

- Xét ΔCAE và ΔCEB, ta có :

EC cạnh chung

AC = CB ( gt )

C1 = C2 ( CD tia phân giác )

=> ΔCAE = ΔCEB ( c-g-c )

- Xét ΔADE và ΔBDE, ta có : 

DB = DA ( gt )

DE chung

D1 = D2 ( hai góc tương ứng )

=> ΔADE = ΔBDE 

C

vãi cả 2015 ạ =))

D