Lời giải:
Chiều dài bằng: $1+\frac{1}{7}=\frac{8}{7}$ chiều rộng

Tổng số phần bằng nhau: $8+7=15$ (phần)

Chiều rộng là:

$420:15\times 7=196$ (m)

Chiều dài là: $420-196=224$ (m)

Diện tích khu vườn đó:
$196\times 224=43904$ (m²)

a: \(=\dfrac{2x+x-2-x-2}{\left(x-2\right)\left(x+2\right)}=\dfrac{2x-4}{\left(x-2\right)\left(x+2\right)}=\dfrac{2}{x+2}\)

b: x^2-x-6=0

=>(x-3)(x+2)=0

=>x=3(nhận) hoặc x=-2(loại)

Khi x=3 thì \(E=\dfrac{2}{3+2}=\dfrac{2}{5}\)

c: Để E nguyên thì \(x+2\in\left\{1;-1;2;-2\right\}\)

=>\(x\in\left\{-1;-3;0;-4\right\}\)

môi trường trong xanh

là nhờ công sức

các cô lao công

là nhờ ý thức 

mỗi người công dân

Trích mẫu thử

Sục khí $CO_2$ tới dư vào mẫu thử : 

- mẫu thử tạo kết tủa trắng là $Ba(OH)_2$
$Ba(OH)_2 + CO_2 \to BaCO_3 + H_2O$

- mẫu thử không hiện tượng gì là $NaCl$

Bạn Trâm học rất tốt .

Em rất thích ăn sốt cà .

cậu ấy học rất dốt.

bạn em học dốt

bà em đốt giấy

bạn có thể chọn rất nhiều

chúc học tốt

Khởi nghĩa Yên Thế là khởi nghĩa của nông dân Yên Thế mang tính chất tự phát. Mà phong trào Cần Vương nghĩa là phò giúp vua

Khởi nghĩa Yên Thế là cuộc khởi nghĩa của nông dân mang tính chất tự phát và mục đích ổn định cuộc sống và bảo vệ xóm làng

Phong trào Cần vương là phong trào giúp vua cứu nước

-25-(x+5) = 415 + 5(x-83)

=> -25-x-5=415+5x-415

=> -30-x-5x = 0

=> -30=6x

=> x = -5 

`-25-(x+5)=415+5(x-83)`

`<=> -25-x-5=415+5x-415`

`<=> -x-5x=415-415+25+5`

`<=> -6x=30`

`<=> x=-5`

-25 - ( x+5 ) = 415 + 5(x- 83)

\(-25-x-5-415-5x+415=0\)

\(-30-6x=0\)

\(6x=-30\)

\(x=-30:6=-5\)

Vậy x=-5

I.Hãy viết hình thức so sánh hơn và nhất của các tính từ sau:

1. So sánh ngang bằng.

a. Mary/tall/her brother.

Mary is as tall as her brother.

b. A lemon/not sweet/ an orange. 

A lemon is not as sweet as an orange.

c. A donkey/not big/ a horse.

A donkey is not as big as a horse.

d. This dress/pretty/that one.

This dress is not as pretty as that one.

e. the weather/not cold/ yesterday.

The weather is not as cold as yesterday.

2. So sánh hơn: (Nhấn mạnh các câu ss hơn)

a. A rose/beautiful/ a weed.

A rose is more beautiful than a weed.

b. A dog/run/quick/ a chicken.

A dog runs more quickly than a chicken.

c. Ba/ friendly/ Nam.

Ba is more friendly than Nam.

d .Your house/far/from school /my house.

Your house if farther from school than my house_.

e. My father / drive/ careful/ I

My father drives more carefully than I do.

3. So sánh nhất:

a. The Nile/long/river/ in the world.

The Nile is the longest river in the world.

b. Lan/ talk/ slow / in my class.

Lan talks the most slowly in my class.

c. English coffee/bad/ of all.

English coffee is the worst of all.

d. Anna/ is/ simple/girl/ in the world.

Anna is the simplest girl in the world.

e. That/high/ mountain in the world.

That is the highest mountain in the world.

II. Complete the sentences using the correct form of the adjectives or adverbs in brackets

(chia về các dạng so sánh đúng)

1. Mary is (pretty) as pretty as her sister

2. A new house is (expensive) more expensive than an old one

3. His job is (important) more important than mine

4. Of the foour ties, I like the red one (well) better

5. Nobody is (happy) happier than Miss Snow

6. Today English is the (international) most international of language

7. John is much (strong) stronger than I thought

8. Benches are (comfortable) more comfortable than arm-chairs

9. Bill is (good) better than you thought

10. Mr. Bush is the (delightful) most delightful person I have ever know

11. Bill is (lazy) lazier and (lazy) lazier.

12. It becomes (hard) harder and (hard) harder to find a job

13. As the conversation went on, he became (talkative) more and more talkative.

14. As I waited for my interview, I became (nervous) more and more nervous.

5. Is the book (interesting) more interesting than the one you read last week?

III. Cirle the best option to complete each sentence:

1. This is the _________ river in the world

a. most long               b. longest                   c. long most               d. longer

2. Do you think older people drive _________ than younger people?

a. slow                                    b. slower                    c. more slow              d. more slowly

3. They all dance well, but John dances _________

a. better                      b. more good             c. the better               d. the best

4. Your computer is more expensive than _________

a. me                           b. my                          c. mine                                   d. myself

5. My car isn’t very new. Your car is _____ than my car

a. newer                     b. older                       c. not new                  d. less new

6. Who is _____ in your class?

a. the interlligentest                                     b. the most intelligent                     

c. more intelligent                                        d. the more intelligent

7. Praja returned home as _________ as he could

a. quick                      b. quicker                  c. quickest                 d. quickly

8. This is _________ elephant I have ever seen

a. the biggest             b. most big                 c. the most big                       d. bigger

9. He ran _________ than his friend

a. fastest                     b. faster                      c. fast                          d. more fast

10. This summer is not as hot _________ last summer

a. as                            b. than                        c. to                             d. like

11. “Could you talk _________ ? I’m learning my lessons”

a. as quietly               b. so quietly              c. more quietly          d. most quietly

12. It is _________ to talk about a problem than to solve it

a. more easier                        b. easier                     c. easy                        d. easiest

13 Jim is five centimeters _________ than Tom

a. higher                     b. taller                       c. tallest                     d. tall

14. Winning a place at university _________ for most students

a. has become as difficult                           b. becomes the most difficulty

c. is becoming more and more difficult    d. will become more difficult

15. The people here are _________ than I expected

a. more nice               b. most nice               c. nicer                                   d. nicest

16. My new boss isn’t as rude _________ my own boss

a. as                            b. so                            c. than                        d. that

20. She was _________ friendly person I’ve ever met

a. the most          b.more                      c.as             d. so