4: =>1-x+3x+3=2x+3

=>2x+4=2x+3

=>0x+1=0(vô lý)

5: =>1+4x-8=2x-3

=>4x-7-2x+3=0

=>2x-4=0

hay x=2(loại)

6: =>7+2x-3=6-2x

=>2x+4+2x-6=0

=>4x-2=0

hay x=1/2(nhận)

Công để bơm nước là

\(A=F.s=50000.5=250000\left(J\right)\)

Thời gian bơm nước là

\(t=\dfrac{A}{P}=\dfrac{250000}{800}=312,5\left(s\right)\)

Công để bơm nước là

Thời gian bơm nước là

61. Do students in Britain like travelling?

- Yes, they do.

62. What is hitchhiking? Is it a good way of travel?

- Hitchhiking is the cheapest way to travel.

- No, it isn't

63. What are bucket shops?

- Bucket shops are the shops which sell cheap airline tickets to countries like the USA, Thailand and Australia.

64. Why are "overland" tours not very comfortble, but special?

- Because you have to share the cooking, but it is a cheap way to see parts of the world that most tourist nver go to.

65. How can we recognize young travellers from Australia?

- We can recognize young travellers from Australia because they often paint a kangaroo symbol somewhere on the van.

B

B

Còn cái này

a: =8/5-2/3=24/15-10/15=14/15

b: =3/5-1/3=9/15-5/15=4/15

c: =1/3-1/5=2/15

d: =6/7-4/9=54/63-28/63=26/63

a.8/5 - 18/27 = 8/5 - 2/3 = 24/15 = 14/15

b. 12/20 - 6/18 = 3/5 - 1/3 = 9/15= 4/15

c. 8/24 - 5/25 = 1/3 - 1/5 = 5/15 - 3/15 = 2/15

d. 18/21 - 12/27 = 6/7 - 4/9 = 54/63 - 28/63 = 26/63

a: =8/5-2/3=24/15-10/15=14/15

b: =3/5-1/3=9/15-5/15=4/15

c: =1/3-1/5=2/15

d: =6/7-4/9=54/63-28/63=26/63

seo câu của tui lại bị xóa mất rồi bài này tui cũng làm hôm qua rùi mè sao ai lại xóa

8/5-2/3=24/15-10/15=14/15
3/5-1/3=9/15-5/15=4/15
1/3-1/5=2/15
6/7-4/9=54/63-28/63=26/63

A, C

Cả hai đều đúng hoặc là đề bài sai

Thôi A nha

giúp tụi mình đi mọi ngừi mình và bạn ý đang cần gấp

a) 8/35

b) 5/8x 3/1= 15/8

c) 7/8- 1/2= 3/8

d) 3/4x 9/8= 27/32

e) 10/9x 5/3= 50/27

a.8/35    ;     27/32

b.15/8    ;     50/27

c.3/8