Bài 20: bỏ dấu ngoặc rồi thu gọn biểu thức: a, A = ( a + b ) - ( a - b ) + ( a - c ) - ( a + c ) b, B = ( a + b - c ) + ( a - b +c ) - ( b + c - a ) - ( a - b - c ) Bài 22: Tính tổng tất cả số nguyên x thỏa mãn: |x| < 2013

Giúp mình bài này với.Cảm ơn nhiều

MÌNH CẦN GẤP AI NHANH TICK LUÔN Ạ I.Here is part of a letter from Jane to her friend Rosa, a teacher in England. Underline the correct alternative. Darwin, 20th December Dear Rosa Hope this find you all well. I suppose by now school (1) will close / will have closed for Christmas and you (2) will be enjoying / will have been enjoying a rest. It’s hard to believe that Tim’s already 18 and that It’s only a few months until he (3) will be leaving / will have been leaving school for college. My main news Is that my brother, John, and his family (4) will have been arriving / will be arriving next Friday as part of their big trip around the world. By the time they get here they (5) will be going / will have been to California and New Zealand. No doubt John’s children (6) will have been planning / will plan it all out for months! They (7) won’t be spending / won’t have spent all their time with me. John has to go to Perth on business, so i (8) will have kept / will be keeping the rest of the family entertained while he’s away. Then they (9) will all be going / will all have been going to Sydney... II. Read this extract from a leisure center brochure and decide which answer A, B, C or D best fits each space. The Burnham Leisure Centre has an impressive range of sports and fitness facilities which are all available to the public at a reasonable price. Bring the family and enjoy the Olympic-size swimming pool or, if you’re a serious athlete, you can (1) ............... throughout the year on the all-weather running (2) ............... You can even (3) ............... snowboarding or skiing on the specially-constructed artificial ski slope. If your game is tennis, you will find there are indoor and outdoor (4) ............... to choose from. For team games, we have three five-a-side football (5) ............... which you will probably have to book in advance because they tend to be very popular. Two basketball teams play at the center, so you can always come along with the kids and (6) ............... a match. If you’re just looking for the chance to get fit, why not take advantage of our superb (7) ............... where you will find all the latest exercise equipment. We also run aerobics classes several times a week which provide low-stress (8) ............... for people of all ages. After your workout, you can relax by taking a sauna. 1. A. exercise B. practice C. train D. work 2. A. ring B. track C. court D. pitch 3. A. go B. play C. do D. make 4. A. pitches B. fields C. rings D. courts 5. A. pitches B. fields C. halls D. courts 6. A. watch B. view C. attend D. see 7. A. court B. gym C. hall D. room 8. A. training B. running C. practice D. Exercise

Giải các phương trình sau: a. (x+1)^2015=4x^2-9X+7 b.(x+1)^2017=x^3-5x+1 c.(x-1)^2015=(2x^2+1)^20

Mọi người giúp mình bài này với ạ! Mình đang cần gấp cảm ơn mn nhiều ạ!

âu 4: Cho tam giác ABC cân tại A (góc A < 90 độ). Kẻ BE vuông góc với AC (E thuộc AC), CD vuông góc với AB (D thuộc AB). Gọi I là giao điểm của BE và CD. a/ Chứng minh rằng: ∆ADC = ∆AEB b/ Chứng minh AI là tia phân giác của góc BAC.

Tìm x,y,z biết 5x^2+3y^2+z^2-4x+6xy-4z+6=0 mình đang cần gấp thanks nha

digi Hazuki Nagisa no tradi có chữ kí

Vẽ anime hoặc chibi, sẵn tiện bác nèo đặt cho cháu tl rùi cháu đặt lại nha:3 Ko vi phạm luật

lm giúp mk vs ak mk sẽ vote 5 sao cảm ơn các bn nhìu