问题
选择题
一元二次方程x2+3x-1=0，通过配方后变形正确的是（ ）
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答案
移项得x2+3x=1，
方程两边都加上（
）2得x2+3x+（3 2
）2=1+（3 2
）2，3 2
所以（x+
）2=3 2
．13 4
故选B．
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一元二次方程x2+3x-1=0，通过配方后变形正确的是（ ）
|
移项得x2+3x=1，
方程两边都加上（
）2得x2+3x+（3 2
）2=1+（3 2
）2，3 2
所以（x+
）2=3 2
．13 4
故选B．
Lilly was a French Canadian girl who grew up in the farming community.When she was 16，her father____her to drop out of school to contribute to the family income.With English as her second language and____education，the____didn’t look bright for Lilly. Lilly’s father was a stubborn man who___took “no” for an answer.He____Lilly to find a job.With small hope of gaining____，each day she would just ride to the city，walk____about and return home at dusk. On one of her____，Lilly saw a sign at a big company.___，she knocked on the very first door.In her____English，Lilly told the office manager she was interested in the secretarial position.The manager ____to give the girl a chance.He directed her to type a letter，and then____.Lilly looked at the clock and saw it was 11∶40 am.She thought everyone would be leaving for____at noon，when she could____away in the crowd.But she knew she should____the letter. On her first try，Lilly____one line of five words and made four mistakes.On her second attempt，she completed a full paragraph，but still made many mistakes.She looked at the clock：11∶55—five minutes to____.Just then the manager walked in.He came directly to Lilly，read the letter and said，“Lilly，you’re doing____work！” With those simple words of encouragement，her desire to escape disappeared and her____began to grow.Lilly thought，“Well，if he thinks it’s good，then it must be good.I think I’ll stay！” Lilly did stay—all because someone had given a____and uncertain girl the gift of selfconfidence when she knocked on the door.
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