làm câu a vs cả câu b thôi nhá các bn hihi

Giúp mình với (hơi ít điểm nhưng mong được các bạn giúp :3) Cho hình thang ABCD là hình thang cân (AD//BC). Lấy điểm E, F lần lượt là trung điểm của AB, CD a) Tứ giác EFCB là hình gì? Vì sao? b) BD cắt È tại I. Chứng minh I là trung điểm của BD c) AC cắt EF tại J. Chứng minh JA = JC và EI = FJ

mn giúp em với ạ thứ 2 em phải nộp r ạ

Ai giải giùm mình câu này với, mình cần gấp

GIÚP ĐI MÀ XIN ĐÓ .............................................

Nếu a//b;b//c thì ta suy ra gì giúp tui với, mai kt 15 phút

Mn giúp mik bài này với nha ! Mik đag cần gấp

49a^2-(3a-b)^2 (a+1)^2-(a-1)^2 (x+5)^2-x^2 (x+2)^2-9x^2 (7x-4)^2-(2x+1)^2 (3x+1)^2-(5x-1)^2

VIII.READING COMPREHENSION. PASSAGE 1: Read the passage below and answer the questions My school Hello. I am Khánh Chi. I'd like to tell you about my school. I go to Trần Quốc Toản Secondary School in Tuy Hòa City, Phú Yên Province. My school is not far from my house. I usually walk to school in the morning. My school has four floors. My classroom is on the second floor. There is a computer lab, a library and a music room in my school. My favorite place is the schoolyard. I like to play soccer there. I really like my school. Question 1: What is the name of Khánh Chi’s school? ______________________________________________________ Question 2: Is her school far from her house? ______________________________________________________ Question 3: How many floors are there in her school? ______________________________________________________ Question 4: Which floor is her classroom on ? ______________________________________________________ Question 5: Where does she play soccer? ______________________________________________________ PASSAGE 3. Read the passage below and answer the questions Hello everyone, my name is Mai Lan. I am eleven years old. I come from Quy Nhơn City. Today, I'm happy to tell you about my school. It is a very beautiful school in the center of the city. There are twenty large classrooms and many function rooms. My school has about eighty teachers. Our teachers are very friendly. Students in my school are very good. At school, I learned many subjects such as Mathematics, Literature, English, Art, Music… I like learning English very much because it is very interesting and important to me. Every day at school is a happy day. I love my school very much. Question 1: How old is Mai Lan? ______________________________________________________ Question 2: Is her school in the countryside? ______________________________________________________ Question 3: How many classrooms are there in her school? ______________________________________________________ Question 4: What is her favorite subject? ______________________________________________________ Question 5: Why does she like that subject? ______________________________________________________

Tìm hiểu vị thế của Việt Nam trong ASEAN từ khi gia nhập cho đến nay