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anhtuanqd
2 năm trước
Cho hình thang ABCD, góc A = góc D = 90°. I là trung điểm AD Chứng minh BI vuông góc AC khi và chỉ khi CI vuông góc BD. Giúp e với ạ
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Ex1: Choose the options that best fit the blanks: 1. The boys are playing games,.................. the girls are watching TV. A. so B. nor C. and 2. I tried my best in the final test,..... the result was not as good as I expected. A. but B. so C. for 3. He lost the key,....... he couldn't get into the house. A. yet B. or C. so 4. She loves comedies,..... her husband is interested in action films. A.for B.yet C.or 5. You must do well in the test,..... you will not graduate. A.so B.or C.for 6. Pop music is so popular,........ the melody is simple and memorable. A.for B.so C.and 7. I should practice more for the competition,..... my health hasn't been excellent recently. A. and B. so C. but 8. You can go to the movies with me,.... you can go to the concert alone. A.and B.or C.so CÁC BẠN GIÚP MIK VỚI 5 SAO LUÔN, CTLHN LUÔN.

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