Mấy thánh học ơi giúp tôi với:
Chứng minh rằng a/b=c/d thì a/b='a+c'/'b+d' và a/b='a-c'/'b-d'
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DT
Đỗ Thanh Hải
CTVVIP
1 tháng 8 2021
Task 1. Choose the odd one out.
1. A. May B. April C. Math D. June
2. A. This B. When C. What D. How
3. A. bicycle B. ride C. dance D. swim
4. A. teacher B. engineer C. hospital D. doctor
5. A. he B. she C. your D. they
Task 2: Circle the correct answers.
. 6……… colour are the jeans?
A. What B. When C. Which
7. She goes to the ………….. to buy some books.
A. bakery B. bookshop C. post office
8. What’s her job? - She is ………..
A. a classroom B. a hospital C. a teacher
9. What’s your favourite………….? - Orange juice.
A. drink B. food C. colour
10. To day, I have got Maths, Art, Science ……. English.
A. but B. and C. or
11. What is your favourite food?
A. It's milk B. It's beef C. It's lemonade D.It pork
12. Let's ………… to the pharmacy I want to buy some medicine.
A. to go B. going. C. go D. went
. What animal do you want ................ ?
13. A. see B. to see C. seeing D. sees
14.Where are you going to do in Hue? -I’m going to ……………..Hue Imperial City.
A. visits B. visited C. visiting D. visit
15. I’m going to stay …………….. a nice hotel.
A. on B. at C. in D. for
Task 3. Read and choose A, B or C.
Sasha and Adam go home after school. Adam throws his backpack on the kitchen floor. Then he pours himself a glass of milk. He eats a snack while he plays a game. Sasha tosses her backpack on her bed. She gets herself a glass of milk and a snack. Then Sasha starts her homework. She likes to finish her homework before supper. Adam needs a break after school. He does his homework after supper. They both work at the kitchen table.
16. Which one is true about Adam?
A. He puts his backpack on his bed
B. He takes a break after school
C. He does his homework before supper
17. What do Adam and Sasha do before supper that is the same?
A. They both do their homework
B. They both drink milk
C. They both play games
18. What does Sasha do after school that is different from Adam?
A. Sasha plays a game, but Adam does not
B. Sasha eats a snack, but Adam does not
C. Sasha does her homework before supper, but Adam does not
Task 4. Choose the correct sentence.
19. wants/clothes./new/Tom/to/buy/
A. Tom clothes wants buy to new.
B. Tom wants buy to new clothes.
C. Tom wants to buy new clothes.
20. the /cinema/Let’s/to/./go/
A. Let’s the cinema go to.
B. The cinema let’s go to.
C. Let’s go to the cinema.
21. much/the/how/is/jumper/?/
A. How much is the jumper?
B. How is much the jumper?
C. How is the jumper much?
22. likes/ because/are/they/fast./My sister/zebras/
A. My sister likes fast because they are zebras.
B. My sister are zebras because they like fast.
C. My sister likes zebra because they are fast.
Task 5: Choose the word that has underlined part pronounced differently
23. A. Christmas B. children C. chair D.chicken
24. A. Drink B. sit C. nice D. City
25. A.they B. think C. there D. this
1 tháng 8 2021
Task 1. Choose the odd one out.
1. A. May B. April C. Math D. June
2. A. This B. When C. What D. How
3. A. bicycle B. ride C. dance D. swim
4. A. teacher B. engineer C. hospital D. doctor
5. A. he B. she C. your D. they
Task 2: Circle the correct answers.
. 6……… colour are the jeans?
A. What B. When C. Which
7. She goes to the ………….. to buy some books.
A. bakery B. bookshop C. post office
8. What’s her job? - She is ………..
A. a classroom B. a hospital C. a teacher
9. What’s your favourite………….? - Orange juice.
A. drink B. food C. colour
10. To day, I have got Maths, Art, Science ……. English.
A. but B. and C. or
11. What is your favourite food?
A. It's milk B. It's beef C. It's lemonade D.It pork
12. Let's ………… to the pharmacy I want to buy some medicine.
A. to go B. going. C. go D. went
. What animal do you want ................ ?
13. A. see B. to see C. seeing D. sees
14.Where are you going to do in Hue? -I’m going to ……………..Hue Imperial City.
A. visits B. visited C. visiting D. visit
15. I’m going to stay …………….. a nice hotel.
A. on B. at C. in D. for
Task 3. Read and choose A, B or C.
Sasha and Adam go home after school. Adam throws his backpack on the kitchen floor. Then he pours himself a glass of milk. He eats a snack while he plays a game. Sasha tosses her backpack on her bed. She gets herself a glass of milk and a snack. Then Sasha starts her homework. She likes to finish her homework before supper. Adam needs a break after school. He does his homework after supper. They both work at the kitchen table.
16. Which one is true about Adam?
A. He puts his backpack on his bed
B. He takes a break after school
C. He does his homework before supper
17. What do Adam and Sasha do before supper that is the same?
A. They both do their homework
B. They both drink milk
C. They both play games
18. What does Sasha do after school that is different from Adam?
A. Sasha plays a game, but Adam does not
B. Sasha eats a snack, but Adam does not
C. Sasha does her homework before supper, but Adam does not
Task 4. Choose the correct sentence.
19. wants/clothes./new/Tom/to/buy/
A. Tom clothes wants buy to new.
B. Tom wants buy to new clothes.
C. Tom wants to buy new clothes.
20. the /cinema/Let’s/to/./go/
A. Let’s the cinema go to.
B. The cinema let’s go to.
C. Let’s go to the cinema.
21. much/the/how/is/jumper/?/
A. How much is the jumper?
B. How is much the jumper?
C. How is the jumper much?
22. likes/ because/are/they/fast./My sister/zebras/
A. My sister likes fast because they are zebras.
B. My sister are zebras because they like fast.
C. My sister likes zebra because they are fast.
Task 5: Choose the word that has underlined part pronounced differently
23. A. Christmas B. children C. chair D.chicken
24. A. Drink B. sit C. nice D. City
25. A.they B. think C. there D. this
8 tháng 10 2021
Ta có: \(\dfrac{a}{b}=\dfrac{c}{d}\Leftrightarrow\dfrac{b}{a}=\dfrac{d}{c}\)
\(\Leftrightarrow1+\dfrac{b}{a}=1+\dfrac{d}{c}\)
\(\Leftrightarrow\dfrac{a+b}{a}=\dfrac{c+d}{c}\)
8 tháng 10 2021
\(\dfrac{a}{b}=\dfrac{c}{d}\Leftrightarrow\dfrac{a}{c}=\dfrac{b}{d}\)
Áp dụng t/c dtsbn:
\(\dfrac{a}{c}=\dfrac{b}{d}=\dfrac{a+b}{c+d}\Leftrightarrow\dfrac{a+b}{a}=\dfrac{c+d}{c}\)
15 tháng 12 2016
xin lỗi nha mình không biết chủ đề nào nên mới chọn đại đây là bài của lớp 7 nha các bạn
21 tháng 7 2019
Đặt \(\frac{a}{b}=\frac{c}{d}=k\)
\(\Rightarrow a=bk;c=dk\)
Ta có:
\(\frac{7a^2+3ab}{11a^2-8b^2}=\frac{7b^2k^2+3\cdot bk\cdot b}{11b^2k^2-8b^2}=\frac{b^2\left(7k^2+3k\right)}{b^2\left(11k^2-8\right)}=\frac{7k^2+3k}{11k^2-8}\left(1\right)\)
\(\frac{7c^2+3cd}{11c^2-8d^2}=\frac{7d^2k^2+3dk\cdot d}{11d^2k^2-8d^2}=\frac{d^2\left(7k^2+3k\right)}{d^2\left(11k^2-8\right)}=\frac{7k^2+3k}{11k^2-8}\left(2\right)\)
Từ \(\left(1\right);\left(2\right)\Rightarrowđpcm\)
Mấy bài khác tương tự
6 tháng 12 2018
quá đơn giản
cho 5 k giải cho
(mình trong đội tuyển toán đó nhe nên làm theo đi)
O
0
a gặp nhiều rồi , nhưng dài lắm chú ak
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