mình làm những bài bn chưa lm nhé

9B

10A

bài 2

have repainted

bàii 3

ride - walikking

swimming

watch

2 have repainted

4 have done 

8 have stepped

9 have you ever played

7) 1 riding -walking

2 swimming

3 watching

8)

2 my mother doesn't like listening to music

5 doing more exercises makes you healthier

còn lại ok nha

chịu ???????????????????

Bài 3: 

a: Ta có: ΔABC vuông tại A

nên \(\widehat{B}+\widehat{C}=90^0\)

hay \(\widehat{B}=60^0\)

Xét ΔABC vuông tại A có 

\(AB=AC\cdot\tan30^0\)

\(=\dfrac{10\sqrt{3}}{3}\left(cm\right)\)

Áp dụng định lí Pytago vào ΔABC vuông tại A, ta được:

\(AB^2+AC^2=BC^2\)

\(\Leftrightarrow BC=\dfrac{20\sqrt{3}}{3}\left(cm\right)\)

XIV.

1. Her sister is more beautiful than her

2. English exercises is more difficult than Literature exercises

3. My new class is bigger tham my old class

4. Phi is more handsome than anybody in the class

5. Loan is taller than anyone in the family

IV.

3. French is not as difficult as English

4. That house is bigger than this house

5. A new house is more expensive than an old house

6. Yesterday is not as hot as today

7. My sister is taller than me

8. Girls are not as strong as boys

X.

1. Lesson 1 is not as long as Lesson 2

2. Ha Noi is smaller than HCM City

3. Old English is not as difficult as new French

4. Quang is not as thin as Quan

5. Your computer is more expensive than my computer

XI.

3. Minh is thinner than Hoang

4. Driving a motorbike is not as difficult as driving a car

XII.

1. Boys are stronger than girls

2. I am more intelligent than my sister

3. A new house is more expensive than an old house

4. English is more difficult than French

5. That river is longer than this river
6. New films are more interesting than old films 

XIII.

3. Quan is the most intelligent student in my school

4. HCM City is the biggest city in VN

1/

Để hàm số trên đồng biến 

Thì m-1 > 0 ⇔ m>1

2/

a,<bạn tự vẽ>

b,Theo phương trình hoành độ giao điểm

\(2x=-x+3\Leftrightarrow3x=3\Leftrightarrow x=1\)

Thay x=1 vào y=2x

y=2.1=2

Vậy tọa độ giao điểm A là (1;2)

3/ Để (d) đi qua điểm M (1;-2)

Thì x=1 và y=-2

Thay x=1 và y=-2 vào (d)

\(-2=a\cdot1+1\Leftrightarrow a=-3\)

vậy ....

Bài 1:

Để hàm số bậc nhất \(y=\left(m-1\right)x+3\) đồng biến.

=> \(m-1>0.\)

<=> \(m>1.\)

Bài 2:

b) Xét phương trình hoành độ giao điểm của 2 hàm số trên ta có:

       \(\text{2x = -x + 3.}\)

<=> \(\text{2x + x - 3= 0.}\)

<=> \(\text{3x - 3 = 0.}\)

<=> \(x=1.\)

=>   \(y=2.\)

Vậy A(1; 2).

Bài 3:

Vì (d) đi qua điểm M(1; -2).

=> -2 = a. 1 + 1.

<=> a = -3.

Vậy a = -3. 

Bài 1:

Cường độ dòng điện qua điện trở: I = U : R = 12 : 60 = 0,2 (A)

Bài 2:

Điện trở tương đương: R_tđ = R₁ + R₂ = 3 + 5 = 8 (\(\Omega\))

Cường độ dòng điện qua mạch chính: I = U : R_tđ = 12 : 8 = 1,5 (A)

Bài 3:

Điện trửo tương đương: R_tđ = (R₁.R₂) : (R₁ + R₂) = (3.6) : (3 + 6) = 2 (\(\Omega\))

Có: U = U₁ = U₂ = 12V (Vì R₁//R₂)

Cường độ dòng điện qua mạch chính và các mạch rẽ:

I = U : R_tđ = 12 : 2 = 6 (A)

I₁ = U₁ : R₂ = 12 : 3 = 4(A)

I₂ = U₂ : R₂ = 12 : 6 = 2(A)

like playing soccer, don't you
goes to school late, doesn't he
can swim very well, can't you
is going to the party, isn't she
was published in Germany in 1550, wasn't it
are sold all over the world, aren't they
have been built this year, haven't they
was given a book, wasn't he 
were bought by Mrs Brown yesterday, weren't they
is used everyday, isn't it