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问题 填空题
反比例函数y=
-5
x
的图象与直线y=kx相交于A（x1，y1），B（x2，y2），则7x1y2+2x2y1=______．
答案

根据题意，x1=-x2，y1=-y2，并且x1y1=x2y2=-5，

所以x1y2=-x1y1，x2y1=-x1y1，

7x1y2+2x2y1=-7x1y1-2x1y1=-7×（-5）-2×（-5）=45．

故答案为：45．

填空题

阅读下面短文，并借助上下文补充所缺信息。每个空只能填写一个形式正确、意义相符的单词。

How do you usually go to小题1:______________? Some of us go to schoo小题2:_________ bus. Others may go to school in their fathers’ cars. If you go travelling to Beijing, what kind of transportations will you choose? A plane or a小题3:__________ ? I think taking a train is funnier than taking a plane. And the price of the ticket is much 小题4:___________ than that of a plane. Also, you can enjoy the beautiful sights through the 小题5: _____________ along the railway.

Nowadays, the high-speed railway is小题6:_________. According to the definition, the high-speed railway refers to a new type of the railway system, owning the rate over 200 kilometers per 小题7:_____________. In the early 21st century, almost none of the railway systems had a rate more than 200 kilometers per hour.

I believe, 小题8:________ the help of the science and technology, our railway system will become more and 小题9:_______ advanced. It will make our 小题10:________more and more convenient.
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单项选择题

以下关于健康相关行为改变知-信-行模式的描述中，错误的是（）

A."知"指知识、学习

B."信"指信念、态度

C."行"指行为、行动

D."信"是基础

E."行"是目标
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