Một mảnh đất hình tam giác có S=756m2, đáy tam giác bằng 42m. Để S mảnh đất tăng thêm 90m2 thì cạnh đáy tăng thêm bao nhiêu mét?
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Bài 1: tìm lỗi sai
1. She goes to visit her grandmother and grandfather next week
=> will go
2. Which place is Phuong and Mai going to visit firts?
=> are
3. They are going in vacation this summer
=> on
4. He wants visit the temple and take some photos
=> to visit
5. They always are going to have a picnic in the park on the weekend
=> \(\varnothing\)
6. It is on of the higher mountains in the world
=> highest
7. This city has a population for 6.3 milion
=> of
8. She always go to Hong Kong on summer vacation
=> goes
9. The River Nile is 6,437 kilometers length
=> long
10. Tomorrow, I am going to visiting the Tower of LonDon
=> am going to visit
1. Every moring, my father (have) __has______ a cup of coffee but today he (drink) _drinks______ milk
2. At the moment, I (read) __am reading_______ a book and my brother (watch) _is watching_______ TV
3. Hoa (live) lives______ in Hanoi, and Ha (live) __lives_____ in HCM City.
4. Hung and his friend (play) _play____ badminton
5. They usually (get up) _____get up_______ at 6.00 in the morning.
6. Ha never (go) _goes_____ fishing in the winter but she always (do) _does______ it in the summer.
7.My teacher (tell) _tells______ Hoa about Math.
8. There (be) _are_______ animals in the circus.
9. __What__does_____ he (watch) __watch_____ TV at 7.00 every morning ?
10. What __does______ she (do) _do____ at 7.00 a.m ?
11. How old _is_____ she ?
12. How __is_____ she ?
13. MY children (go) _goes______ to school by bike
14. We (go) _go______ to supermarket to buy some food.
15. Mr.Hien (go) _goes_____ on business to Hanoi every month
16. Ha () ___s___ coffee very much, but I (not ) _don't _____ it
17. She () _s____ Tea, but she (not ) _don't ______ coffee
18. I (love) _love_____ cats, but I ( not love) _don't love______ dogs
19. Everyday, I (go) _go_____ to school on foot, but today I (go) _go_____ to school by bike
20. Who do you ( wait) _wait____ for Nam?
- No, I (wait) _wait______ for Mr.Hai
Gọi chiều dài là a (m) ; chiều rộng là b(m)
Ta có : Nửa chu vi hình chữ nhật là : 150 : 2 = 75 m
=> a + b = 75 (1)
mà 3 x a = 2 x b
Lấy (1) nhân 3 theo vế ta có :
3 x (a + b) = 3 x 75
=> 3 x a + 3 x b = 225
=> 2 x b + 3 x b = 225 (Vì 3 x a = 2 x b)
=> 5 x b = 225
=> b = 45
=> a = 75 - 45 = 30
Vậy chiều dài dài 30 m ; chiều rộng dài 45 m ???
Thể tích của bể là : 2 x 1,5 x 1 = 3 m3
Thời gian để bể đầy nước là : 3 : 0,5 = 6 giờ
Thể tích bể nước là
\(V=2\times1,5\times1=3\left(m^3\right)\)
Thời gian bể đầy nước là:
\(3\div0,5=6\)(giờ)
Chiều cao của tam giác ban đầu là :
756 x 2 : 42 = 36 m
Để S mảnh đất tăng thêm 90 m2
=> Đáy phải tăng thêm 90 x 2 : 36 = 5 m