Cho tam giác ABC. Lấy I là trung điểm của AC, điểm J thuộc cạnh BC sao cho: BC = 3BJ; BI cắt AJ tại điểm O. Đường thẳng qua I song song với AJ cắt BC tại N. a) Chứng minh N là trung điểm của CJ b) Chứng minh O là trung điểm của BI (GIÚP MÌNH VỚI, MÌNH CẢM ƠN)

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giup mình với 1. because / she is going / she has / the doctor / to see / a high fever. She is going____________________________________________________________ 2. are / after / drinking tea/ interested in/ meals/ my grandparents. My grandparents________________________________________________________ 3. to recycle/“Go green”/ bottles, cans/ encourages people/ and paper. “Go green”_____________________________________________________________ 4. my brother/ so far / this year / has donated / three times / blood. This year_________________________________________________________________ 5. with/ shouldn’t/seafood allergy/ shrimps or crabs/ people/ eat. People ___________________________________________________________________ 6.. street children/ “Be a Buddy”/ with food / provides/ and warm clothes. “Be a Buddy” ___________________________________________________________ 7.. clean,/ she rarely/ herself/ she keeps/ so/ gets flu/. She keeps_______________________________________________________________ 8. many mountains/ has climbed/ in Vietnam/ Jack/ so far. Jack___________________________________________________________________ 9. have / for/ I / English / learned / 3 months I ........................................................................................................................................... 10. is / in social life/ Community service/ very important Community.......................................................................................................................................... 11. experience/ a/ was / Being a volunteer / wonderful Being a volunteer................................................................................................................................. 12. likes/ cold water/ drinking/ Bill Bill ........................................................................................................................................ 13. to / so much / It’s / eat / unhealthy / junk food It’s……………………………………………………………………………………………. 14. homeless children / give away / Let’s/ clothes / to/ warm Let’s…………………………………………………………………………………………. 15. in / people/ stay/ helps / shape / Doing exercises Doing exercises……………………………………………………………………………………