Sunshine
23 phút trước

`a, x + 7 - 25 = 13`

`x + 7 = 38`

`x = 31`

`b, 98 - (x+4) = 120`

`x + 4 = -22`

`x = -26`

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Đăng Khoa
13 phút trước

3. Last night I ...........dinner with my friends.A. have B. hadC. to have D. having

34. Are Mum and Dad ......... at the moment ?A. workingB. workC. worksD. worked

35. Mai is hungry. She’d like some...........A. noodleB. tea C. vegetable D. hot drink

36. Ellen is very friendly. She is ................ rude.A. sometimesB. alwaysC. neverD. usually

37. She listens to music......................A. two times a week B. a week twiceC. twice a weekD. two a week

38. Luke can’t talk to you now. He .................. a bath.A. havingB. is havingC. hasD. had

39. When are you .........vacation with your family, Lan?A. onB. byC. withD. to

40.They arrived in Ho Chi Minh city........................Monday morning.A. inB. onC. aD. to

41. I suggest________some money for poor children.A. raiseB. to raiseC. raisedD. raising

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Sunshine
21 phút trước

`a, x xx 6,5 = 227,5`

`x= 35`

`b, 22,6 : x = 14,125`

`x = 1,6`

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Nguyễn Lê Huy Hoàng
7 phút trước

\(a,x.1,23+x.5,27=227,5\\ \Rightarrow x.\left(1,23+5,27\right)x=227,5\\ \Rightarrow6,5x=227,5\\ \Rightarrow x=227,5:6,5=35\)

\(b,36,8:x-14,2:x=14,125\\ \Rightarrow\left(36,8-14,2\right):x=14,125\\ \Rightarrow22,6:x=14,125\\ \Rightarrow x=22,6:14,125=1,6\)

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POP POP
7 phút trước

\(2Al+6HCl\rightarrow2AlCl_3+3H_2\\ n_{Al}=\dfrac{5,4}{27}=0,2\left(mol\right);n_{HCl}=\dfrac{25,55}{36,5}=0,7\left(mol\right)\\ Vì:\dfrac{0,2}{2}< \dfrac{0,7}{6}\Rightarrow HCldư\\ n_{AlCl_3}=n_{Al}=0,2\left(mol\right)\\ m=m_{muối}=m_{AlCl_3}=0,2.133,5=26,7\left(g\right)\)

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