问题
解答题
（1）计算：
（2）解方程：x2+4x=5． |
答案
（1）原式=2
-1+2
=2
-1；2
（2）由原方程，得
x2+4x+22=5+22，
配方，得
（x+2）2=9，
开方，得
x+2=±3，
解得，x1=1，x2=-5．
搜题请搜索小程序“爱下问搜题”
（1）计算：
（2）解方程：x2+4x=5． |
（1）原式=2
-1+2
=2
-1；2
（2）由原方程，得
x2+4x+22=5+22，
配方，得
（x+2）2=9，
开方，得
x+2=±3，
解得，x1=1，x2=-5．
Mr. Cronin has a clock shop in the center of the town. He tries his best to 36 it well. He often receives the customers(顾客) 37 and people like to buy 38 in his shop. It was a cold day and 39 people would go out to do some _40_. Mr. Black, one of Mr. Cronin’s_41_, came to the shop. He knew the man was_42_ his miserliness (吝啬). But he tried to persuade (说服) him to buy a watch in his shop. “You’d better buy a watch for 43 _, Mr. Black,” said Mr. Cronin. “It’ll be _44_ to you whenever.” “No, no,” said Mr. Black. “I’ll _45_need any watches.” “But how do you know when it’s time to _46_?” “The people who live around me always _47_ their televisions at seven for the news. So I can hear the announcer(播音员) say, “ The time is seven o’clock.. Here is the news.” “But you don’t know when to go to work.” “That’s _48_,” Mr. Black said with a smile. “It takes me ten minutes to _49_ and shave（刮脸）. I have breakfast at twenty past seven. I get to the bus stop at twenty to eight and fifteen minutes later arrive at my office and _50_ working.” “When do you _51_ your office, then?” “There’s a _52_ near it, its siren(汽笛) can tell me the right time.” “How do you know the time if you _53_ in the middle of the night?” “I always put a stick by my bed” “But a stick can’t tell you the time” “You’re _54_. But I can use it to knock on your wall. You always _55_, “What are you knocking on my wall for at two in the night?” 小题1:A. watch B. manage C. build D repair
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