3/1 bn ơi

a, (2x +1)^2= 2x^2 + 2×2x×1+1^2

=(2x)^2 + 4x + 1

1.No because it is dangerous and can cause accident  

2.i prefer watching because home it is comfortable and cheap

3. I think it is good because it keeps culture alive and bring people together

4.they are clean , safe and help protect  the environments

In the picture , people are singing at the hội lim festival. They wear traditional clothes and hold round fans. The stage is colorful and looks very lively 

1.My name is Phạm Đức Tâm

2.i usually ride my bicycle every day

It is about 1 kilometers from my house to school

3.i like action films and comedies  the most

4.i joinned the mid autumn festival

5.we use electricity and gas at the home  

Ko bt