直线l经过点A（-2，1），斜率为12，则点B（-1，1）到直线的距离为_____爱下问搜题

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问题填空题

直线l经过点A（-2，1），斜率为

1

2

，则点B（-1，1）到直线的距离为______．

答案

由直线方程的点斜式可得，直线l的方程y-1=

1

2

（x+2）即x-2y+4=0

由点到直线的距离公式可得，点B（-1，1）到直线l的距离d=

|-1-2+4|

5

=

5

5

故答案为：

5

5

选择题

能用来分离Fe³⁺和Al³⁺离子的试剂是

A．KSCN

B．NH₃· H₂O

C．NaOH溶液

D．H₂S溶液

完形填空

完形填空（共20小题；每小题1.5分，满分30分）
阅读下面短文，从短文后各题所给的四个选项（A、B、C和D）中，选出可以填入空白处的最佳选项，并在答题卡上将该项涂黑。
Today we had an American family, the Robinsons, for Sunday dinner. Mr. Robinson is my mother’s co-worker.
Mr. and Mrs. Robinson and their two young       came at about 6:00 PM. Mrs. Robinson gave Mum a bunch of fresh flowers,      color,freshness and their good will. Mum did the       and it was left to ourselves to get to know each other. I soon      on well with the two girls Judy and Annie.
Mrs. Robinson was much         than her husband. There was a moment of embarrassment when Granny asked about her       . Mum was about to apologize   Mrs. Robinson laughed and said it was quite all right and that she had been in     long enough to know it was the Chinese custom. She       told us that she was 32, though her husband was 52.
And of course they entirely       the dinner. Like a perfect Chinese hostess, Mum and especially Granny       stuffing(填) them with food and urging them to eat and to drink, apologizing all the time that it’s a homely meal.       , Mrs. Robinson said to Mum, “In the West any hostess would be proud of such a feast instead of apologizing for it, and we don’t urge the guests to eat or drink.       so many good things before me, I certainly don’t need any urging. The problem is how to prevent     overeating owing to your keeping putting food into my bowl.” We
all       laughter at that.
When they       to leave, they thanked us not only for the excellent dinner, but for giving them such a nice      . Besides, they insisted on giving every one of us a hug and a       , which did embarrass me. But I think Granny was really    when they kissed her.
It’s surprising how a little good will on both sides can         language and cultural barriers.

C．introduction

D．instruction