cho tam giác abc có góc a = 90° . M là trung điểm BC . D , E lần lượt là trung điểm của AB , AC . a) chứng minh tứ giác ADHE là hcn b) lấy I đối xứng D qua H . Tứ giác ADIC là hình gì ? c) lấy K đối xứng E qua H . Tứ giác AEKB là hình gì ? d) chứng minh DK // EI

Các câu hỏi liên quan

I/ Correct the verb form in parentheses. 1. The Sun ( rise)……….in the East. It (not rise)…………………in the west. 2. She (speak)…………….French, she (not speak)……………………English. 3. He (watch)……………TV and his wife (wash)……………clothes. 4. Daisy(not watch)…………………..TV and Jane (not do)………………… her homework. 5. Mr.Ba always (have)………….coffee for breakfast, He ( not have)……………….milk. 6. We (not watch)…………………TV in the morning.We (read)………..newspapers. 7. What (do)………this sentence mean? It(mean)……………that you’re lucky. 8. Hoa (study)……………English, she (not study)………………French. 9. I think he ( be)………a doctor, he (not be)…………an engineer. 10. Mothers often(tell)………….small children Fairy tales before bedtime. II/Put the verbs in parentheses into present continuous tense. 1. 1.Look! Somebody (come)……………….. 2. It (rain)……………now, take my umbrella please. 3. Keep quiet ! we (listen)………………to music. 4. Marry (write) ……………………..her lessons at this moment. 5. Be careful! Water ( boil)………………. 6. Don’t bother me, please.I (work)……………… 7. Mom is cooking dinner while Dad ( wash)………………..vegetables. 8. What……..you (do)…………now? I’m (look)…………..for my key. 9. Mrs. Thu is always (lose)…………….her hat. 10. Nga (not watch)………………………..TV now. lm cái cho zui đi mà