Cho tam giác ABC nhọn ( AB<AC). Tia phân giác của góc BAC cắt BC tại D. trên cạnh AC lấy điểm E sao cho AE =AB a) chứng minh rằng ABD = AED b) hai tia AB và ED cắt nhau tại F . Chứng minh: tam giác DBF = tam giác DEC

Các câu hỏi liên quan

II. Choose the best answer. 0. What lessons do you ............................ today? A. have B. has C. having D. had 1. Boy: How many lessons does Mary have today? Girl: She has …………………………. A. five B. three times C. Music D. every week. 2. Boy: How…………………………..do you have Vietnamese? Girl: I have it four times a week. A. many B. much C. long D. often 3. How do you practise ………………………………….? A. to speak B. speaking C. spoke D. speak 4. What……………….Miss Hien reading? A. am B. are C. is D. was 5.Boy: What is Snow White……………………………..? Girl: She is very gentle and kind. A. like B. doing C. reading D. have III. Read and choose the best answer A, B, C or D. I (0) …….had….. a wonderful holiday with my friends in Nha Trang last summer. We went there (1) ………………..….plane and it took us two hours to get there. We stayed at my friend’s house. In the morning, we got up (2)………………………… 6 o’clock to see sunrise then went (3) ………………We also played volleyball on the beach and (4) ………………..many photos. In the evening, we went along the seaside and ate a lot of nice food. The trip was short (5)…………………………it was very interesting. 0. A. have B. had C. having D. will have 1. A. on B. by C. of D. in 2. A. at B. in C. on D. about 3. A. to swim B. swim C. swims D. swimming 4. A. take B. taked C. took D. will take 5. A. but B. because C. or D. then