Bài 2: Mình nghĩ câu a là a+2b-3c=-20

a) Ta có: a/2 = b/3 = c/4 = 2b/6 = 3c/12 = a + 2b - 3c/ 2 + 6 - 12 = -20/-4 = 5

a/2 = 5 => a = 2 . 5 = 10

b/3 = 5 => b = 5 . 3 = 15

c/4 = 5 => c = 5 . 4 = 20

Vậy a = 10; b = 15; c = 20

b) Ta có: a/2 = b/3 => a/10 = b/15

              b/5 = c/4 => b/15 = c/12

=> a/10 = b/15 = c/12 = a - b + c / 10 - 15 + 12 = -49/7 = -7

a/10 = -7 => a = -7 . 10 = -70

b/15 = -7 => b = -7 . 15 = -105

c/12 = -7 => c = -7 . 12 = -84

Vậy a = -70; b = -105; c = -84.

Trang có số cái kẹo là 1+1=2(cái kéo)

co 13 hinh chu nhat

1. An said to Hoa that he wasn't told to be there at 9 p.m that night

2. I said to my brother that he ought to clean his room then

3. Huy said to Chau that his parents were proud of his good report

4. The woman said to Phu that she expected to see him the next day

5. The teacher told him that he had to ask him/her to help him

6. He said to her that they didn't watch that film with their friends again

=>39 nha bạn

....k tui nha ^_

làm ơn

100000

Như quỳnh ơi, mk làm sai câu c, cậu thay x =8 là x= 4 nha

Cảm ơn cậu nhìu, chúc cậu học tốt!

Ừ, cảm ơn nhé ! Mk đi học Toán nâng cao í mà

a) ta có: 34= 2 * 17

72 = 2^3 * 3^2

132 = 2^2 * 3* 11 

=> ƯCLN(34; 72; 132) = 2 

=> ƯC(34; 72; 132) = Ư(2)= {+-1; +-2}

b) 9 = 3^2

18 = 2* 3^2 

72 = 2^3 * 3^2

=> ƯCLN (9;18;72) = 3^2 = 9 

=> ƯC(9;18;72) = Ư(9) ={+-1; +-3; +-9}

2 , 4 , 6 , 8 , 10 , 12 , 14 , 16 , 18 , 20 , 22 , 24 , 26 , 28