Topic 1: To have good health, everyone needs to maintain a healthy lifestyle. To be healthy, the diet must contain an appropriate amount of calories and a variety of plant-based foods. Secondly, you must sleep well and sleep for 8 hours a day to stay healthy. When you get enough sleep, your body is rested and re-energized after every day of activity. Therefore, reasonable rest and enough sleep is an extremely necessary medicine for health. Third, healthy people always make sure to be active for at least 30 minutes a day and like to exercise. Exercise contributes to improving health and protecting the body against cardiovascular and respiratory diseases.

Topic 2: In my opinion, customs and traditions are very important. Like other families, we have our own customs and traditions. Firstly, there's a tradition in our family of having lunch together on the second day of Tet. Secondly, we have the custom of spending Sunday together. We usually go to the cinema or go for a picnic. We don't have to do it, but it makes us closer as a family. We all enjoy these customs and traditions because they provide our family with a sense of belonging.
Topic 3: After 4th grade, my mom starts to teach me how to do some small housework in my family. And now, I can do many housework to help my family. After have a good night sleep, I make my bed, in the lunch or the dinner, I set the table. After eating, I will do the dishes, it is easy for me. I also feed my dog and I do all that housework everyday. But in the weekend, I need to hang out the clothes to give my parents a rest. I feel fun when I do housework because it make my parents feel proud of me.

1. If you don't drink more water, you will get more acne.

2. My sister wants to see the terraced fields so she is going to Sa Pa.

3. Unless he spends time on his phone, he will complete his work.

1. If you don't drink more water, you will get more acne.

2. My sister wants to see the terraced fields so she is going to Sa Pa.

3. Unless he spends time on his phone, he will complete his work.

Ta có Ax vuông góc với AC và By song song với AC

Suy ra Ax vuông góc với By suy ra góc AMB = 90 độ

Xét tam giác MAG và tam giác QBM:

MQA​=BMQ​ (so le trong);

MQ là cạnh chung;

AMQ = BQM ( Ax song song với QB )

Suy ra \(\Delta MAQ=\Delta QBM\) (g-c-g)

Suy ra \(\hat{M B Q} = \hat{M A Q} = 9 0^{\circ}\) (2 góc tương ứng)

Xét tứ giác \(A M B Q\) có: \(\hat{Q A M} = \hat{A M B} = \hat{M B Q} = 9 0^{\circ}\)

Suy ra tứ giác \(A M B Q\) là hình chữ nhật.

b) Do tứ giác \(A M B Q\) là hình chữ nhật.

Mà \(P\) là trung điểm AB \(n \hat{e} n\) PQ = 1/2 AB

Xét \(\Delta A I B\) vuông tại \(I\) và có \(I P\) là đường trung tuyến.

Suy ra \(I P = \frac{1}{2} A B\) (2)

Từ (1) và (2) \(\Rightarrow Q P = I P \Rightarrow \Delta P Q I\) cân tại \(P\).

Ta có BM là đường trung tuyến của tam giác ABC

Mà BM=1/2AC nên tam giác ABC có góc B vuông

Suy ra tứ giác ABCD có góc A = góc D = góc B = 90 độ

Suy ra ABCD là hình chữ nhật

Trả lời :

Ta có I là trung điểm của AC hay IA = IC và IH = ID

Suy ra tứ giác AHCD là hình bình hành ( tính chất)

Mà có góc H là góc vuông

Nên hình bình hành AHCD là hình chữ nhật

Vậy đpcm