3. 刘娜同学在计算多项式2x²+3xy-5y²加上另一个多项式时,由于粗心.在线等

“老师你好，我这里有一道数学题想了很久过后还是没想出解题的方法，请老师为我讲解一下！”其实只要你说的诚恳点，老师一定会告诉你.

刘娜：X 王丽：Y
3X=Y+2
Y-8=X+6
解方程得：X=8 Y=22
所以刘娜：8岁 王丽：22岁

可设第二天读了x页,那么可列等式(75+x)×1/4=175-75-x,解出x=65页

Dear Liuna,
I have a conert ticket,which will be held at 7:30 pm on Sunday,Dec.15.The place at which the concert will be held is Guanghua Theater.The concert will be an unforgetable one,for Jay Chou will be on stage then.Please make sure to take Alice to come.
Let's see at the gate of Guanghua Theater,at 7:30 pm on Sunday,Dec.15.No seeing,no departing.
Yours sincerely
Liu Xiaoxiao
Dec.10

I’m Tina.Liu Na and I are good friends.We are in the same school but we are in different classes.We are different.Liu Na always stays at home watching TV .Sometimes she watches TV for three hours a day.And she never does sports.She often eats hamburgers.But I like going out and doing sports three times a week.I never eat junk food.I eat lots of fruit and vegetables.We are different but we are friends.

ls this your red wacth ?
found:red wacth
please call Li Na
phone#235-0285
(一定要这个格式,你是不是初一的,我是,我也要写）

倩的鑫之所在
我与你情倩一鑫
相守在倩的鑫语鑫愿
希望喜欢哈~

解题思路：（1）电压表和电流表的读数：确定使用的量程，确定每一个大格和每一个小格各代表多少．
（2）知道电压和电流，根据R=[U/I]，求出电阻大小．

电压表使用的0～3V量程，每一个大格代表1V，每一个小格代表0.1V，电压为2.4V．
电流表使用的0～0.6A量程，每一个大格代表0.2A，每一个小格代表0.02A，电流为0.12A．
R=[U/I]=[2.4V/0.12A]=20Ω．
故答案为：2.4；0.12；20．

点评：
本题考点： 欧姆定律的变形公式．

考点点评： 电流表和电压表的读数、欧姆定律都是电学最基础的内容，一定要熟练掌握．

A survey of active chores
A, problem
For the only child in the US, are generally "live on the labour of others", all are the parents of a pearl in the palm, like the little prince, the littleprincess, living a happy life, remain free. But, can take the initiative to help parents do houseworkclassmates how many? So, a few students in our groupmade a survey of the active housework situation.
Two, investigation method
1 were carefully observed the number of students take the initiative to do the housework.
2 visiting parents, children can actively,conscientiously do the housework, housework once a few days.
3 through the network, books and magazines to do housework for us.
Whether the 4 visiting students like to do housework.
Three, the survey and data collection
Housework on take the initiative to do the students in this class
Information channel
Design
The specific content
Come to conclusion
Analysis
Observation
The number of students take the initiative to do the housework
Only a dozen students can take the initiative to dothe housework
A few students do housework
The majority of students are doesn't love to do housework
Visiting parents
If their children can take the initiative to dohousework, do housework, how long do a housework.
Some of the students two days to do a chore, but many students can not take the initiative to do the housework.
Many students are not able to take the initiative to help parents do housework, and most of the studentsdo not seriously, can not do the housework.
Many students can not take the initiative to dohousework, a few students can do some housework oncein five days, the majority of students doesn't loveto do housework.
Network
Take the initiative to do housework
1, can exercise their self-care ability. 2, can make oneself become diligent.
3, to alleviate some of the burden for my parents.
Take the initiative to do many housework benefits, in general do housework is a good thing.
Many of the benefits of doing housework, do houseworkis a happy thing.
Visiting students
Whether you like to do housework
Many students think that housework is a difficult thing, doesn't like doing housework.
The students think actively doing housework is not good, can not take the initiative to do the housework.
Many students doesn't like doing housework
Four, the conclusion
1, many students can not take the initiative to do housework, seriously, just rely on their parents.
2, a small number of students can do some housework once in five days, most of the students are didn't love to do housework.
3, many of the benefits of doing housework, do housework is a happy thing.
4, do the housework can temper our will, we canstrengthen the sense of responsibility, can enhance our confidence, but also enrich the knowledge of life, the development of intelligence. If you will do the housework, but also active, earnest, grew up in the work will also have a rational.
This is my first time to write the report, if writingis not enough, please you valuable advice, thank you!
Liu na.