5:

=1,75h+1,75h+1,75h*8

=1,75h*10=17,5h

4:

Đáy bé là 80*3/4=60m

Diện tích là (80+60)*48/2=3360m²

Khối lượng thóc thu được là:

3360:100*65=2184kg

Bài 3: 

a: Ta có: M và N đối xứng nhau qua AB

nên AB là đường trung trực của MN

Suy ra: MN\(\perp\)AB tại H và H là trung điểm của MN

mà AB\(\perp\)AC

nên MN//AC

1 D

2 A

3 B

1 A

2 C

3 D

4 A

5 C

6 D

7 A

1. D

2. A

3. B

1. A

2. C

3. D

4. A

5. C

6. D

7. A

a: \(\Leftrightarrow9-x=6\)

hay x=3

e: \(\Leftrightarrow2^x=32\)

hay x=5

1. The use of electricity will reduce to save up energy

2. I think we will not have electric taxis until the year 2050

3. Ko rõ

4. Traffic jam is one of the most common issue of the big city in the world

5. 

The use of electricity will be reduced to save energy

I think we won't have electric taxis until the year of 2050

You have not buy the food, haven't you?

Traffic jam is one of the most common issus of big city around the world

There are too many people using the road and it is one of the main reasons causing traffic jams

We can solve the traffic problem by encouraging people to use bicycles rather than cars in short trips

People should use public transports to reduce the number of private vehicles on the road

Moving big companies and factories from cities to the countryside can also help to reduce traffic jams

1: \(\left(x+1\right)^3=x^3+3x^2+3x+1\)

2: \(\left(x-1\right)^3=x^3-3x^2+3x-1\)

3: \(x^3+1=\left(x+1\right)\left(x^2-x+1\right)\)

4: \(x^3-1=\left(x-1\right)\left(x^2+x+1\right)\)

5: \(\left(x+2\right)^3=x^3+6x^2+12x+8\)

a: 12h: 0 độ

10h: 60 đọ

6h: 180 độ

5h: 150 độ

b: 

a: góc nhọn: góc yMz; góc tMz

b: góc vuông: góc yMt, góc xMt

c: góc tù: góc xMz

d: góc bẹt: góc xMy