Cho hình thang ABCD (AB song song CD) có A - D = 20 độ, B = 2C. Tính các góc của hình thang.

He took the exam before he went on a trip to Nha Trang.

= [(2x)² + 2.2x.3 + 3² ] - [ x² - 2.x.1 + 1² ]

= [4x² + 12x + 9] - [x² - 2x + 1]

= 4x² + 12x + 9 - x² + 2x -1

= 3x² + 14x + 8

Cho tứ giác ABCD, có B - A = 70 độ, A = C, B + D = 200 độ. Tính các góc A, B, C, D.

1. The streets are cleaned by the workers every day.

2. Your bike will be repaired by me tomorrow afternoon.

3. I am happy to have passed all the exams.

Tìm giá trị nhỏ nhất của: 

a) A = x² + 4x - 4

b) B = x² + 2y² - 6x + y + 2022

1. The coffee is so hot that the children can't drink it.

2. My brother is so strong that he can lift this heavy table.

3. It is such an interesting play that you should see it.

4. It is such a heavy suitcase that nobody can carry it upstairs.

5. My brother is so intelligent that he can do this difficult exercise.

6. The man is so poor that he can't buy a new bike for his wife.

7. It is such a short coat that he can't wear it.

8. The tests were so difficult that we couldn't do them.

9. He is such a lazy boy that everybody hates him.

10. She is such an intelligent girl that she can do this difficult exercise.