15. Tìm số nghịch đảo: a) 3/7 + 5/4 b) 2/3 - 1/4 c) -3/2 . 7/6

17. Tính a) -2/5 : 11/6 b) -4/13 : -1/13 c) ( -2 ) : 11/6 d) -14/13 : 7 đ) -5/19 : 20 g) 24 : -8/9 h) 9/11 : 7/22

`C=x^2 y^2 + 2xy - 3x^2 y + 4xy -5+3x^2 y^2 + x^2 y` `D=2xy+3-8xy-3(xy)^2 + 5x^2 y + 1` Tính giá trị của `E` khi `x/2 + y/3 = 0` và `2x-y=-7`

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1 It is interesting.....fishing with you a. go b. going c. to go d. goes 2 Japan has a big......industry a. car-making b. make-car c. making-car d. car-make 3 Last summer vacations, we decided....to DaLat city a. to get b. to go c. to do 4 Can i get you some drink?-.......... A. good b. Yes, please c. OK d. never mind 5 i saw him......the flowers in the garden a. watering b. watered c. be watered d. be watering 6 They are tired....doing the same thing every day a. in b. of c. at d. with Làm và giải thích hộ mình

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