China is a very important place in the modern world. The country
is massive and measures 9,600,000 square kilometres. It has a
massive population: approximately 1.3 billion, the largest in the
world. China has a fast growing economy. China is a beautiful
country filled with large population and a strong cultural
background. Though China was largely isolated from the rest of the
world after the communist revolution, it has since opened its doors
to the world once again. With the largest population of people in
the world and the largest land area the the geography of China is
as vast as it history. The history and cultural traditions of China
have been studied and written about for a long time. China has
beautifully colossal landscape and it is varied: high mountains to
rainforests, cold deserts to fertile plains and great rivers,
especially the Huang (Yellow River). There human landscapes which
are also varied: the capital Beijing, and Shanghai to tiny rural
villages. China has 668 cities in total. 13 of them have
populations of more than 2 million people. These include: Shanghai,
Guangzhou, Xi'an, Wuhan, and Chengdu. The main religions of China
are: Taoism and Buddhism. The main languages they speak are:
Mandarin and Standard Chinese. The president is Hu Jintao. Main
Crops are: Rice, wheat, potatoes, maize, tobacco, soybeans,
peanuts, tea, millet, barley, apples, cotton, oilseed, pork and
fish. There national animal is the Panda. You can take a trip to
the amazing and huge Great Wall of China.
Hope this helps you.

1 B

2 D

Phần gạch chân là phần nào?

               Bài 3: 28 mét dây nặng số ki-lô-gam là:

                          0,5 x 28 : 4  = 3,5 (kg)
                  Kết luận: 28 mét dây nặng 3,5 kg

Ta có: \(5x=8y\) 

hay \(\dfrac{x}{8}=\dfrac{y}{5}\)

Áp dụng tính chất dãy tỉ số bằng nhau, ta có:

\(\dfrac{x}{8}=\dfrac{y}{5}=\dfrac{y-x}{5-8}=\dfrac{-15}{-3}=5\)

Do đó:

\(\dfrac{x}{8}=5\Rightarrow x=8.5=40\)

\(\dfrac{y}{5}=5\Rightarrow y=5.5=25\)

Vậy \(x=40\); \(y=25\)

Ta có 5x = 8y

hay x/8 = y/5

Áp dụng tính chất dãy tỉ số bằng nhau, ta được:

x/8 = y/5 = y-x/5-8 = -15/-3=5

do đó:

x/8 = 5 suy ra x = 8,5 = 40

y/5 = 5 suy ra y = 5,5 = 25

Vậy x = 40, y = 25

2 a paper => some paper

3 some => a

4 room => rooms

5 a => any

6 homeworks => homework

 giúp mik với

\(\dfrac{x-3}{5-x}\) = \(\dfrac{5}{7}\) (đk \(x\) ≠ 5)

7.(\(x\) - 3) = 5.(5 - \(x\)) 

7\(x\) - 21 = 25 - 5\(x\)

7\(x\) + 5\(x\) = 25 + 21

   12\(x\)    = 46

       \(x\)     = 46 : 12

        \(x\)    = \(\dfrac{23}{6}\)

\(\dfrac{\left|x-2\right|}{2}\) = \(\dfrac{\left|2x+3\right|}{3}\)

3.|\(x\) - 2| = |2\(x\) + 3|.2

lập bảng ta có:

Theo bảng trên ta có:

       \(x\) < - \(\dfrac{3}{2}\) ⇒ -3\(x\) + 6 = - 4\(x\) - 6

                      -\(3x\) + 4\(x\) = - 6 - 6

                                 \(x\) = -12

      - \(\dfrac{3}{2}\)  < \(x\) < 2 ⇒ 3\(x\) - 6 = - 4\(x\) - 6

                              3\(x\) + 4\(x\) = 6 - 6

                                   7\(x\)   = 0

                                     \(x\)    = 0

       2 < \(x\) ⇒ 3\(x\)- 6 = 4\(x\) + 6

                   4\(x\)  - 3\(x\) = - 6 - 6

                              \(x\) = -12 (loại)

Vậy \(x\) \(\in\) {-12; 0}

Ảnh mờ lắm em ơi, nhìn không nổi em nhé!

Đề mờ quá. Bạn nên gõ hẳn đề ra để mọi người hỗ trợ tốt hơn nhé.

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