将一元二次方程x2-6x-5=0化成(x+a)2=b的形式,则b等于______

题型:填空题

问题:

将一元二次方程x2-6x-5=0化成(x+a)2=b的形式,则b等于______.

考点:一元二次方程的解法
题型:填空题

硒元素是人体必须的微量元素,具有抗癌作用,它的相对原子质量为79,其原子的核外电子数为34,则它的中子数为                    (        )

A.45

B.34

C.79

D.113

题型:填空题

女,29岁,长期乏力。血红蛋白77g/L,平均红细胞血红蛋白浓度26g/dl,平均红细胞体积 63fl。网织红细胞计数2.0%,血清铁51μmol/L (280μg/L),总铁结合力4980μg,/L。诊断应该是

A.溶血性贫血

B.再生障碍性贫血

C.缺铁性贫血

D.慢性病性贫血

E.巨幼细胞贫血

题型:填空题

This was one of my experiences (1) . When I was in my 30s, I was working for a large international company which had its head office in London. I was working in the (2) department.

The company had a training centre which was just outside London. Different courses were held there throughout (3) and I (4) go on one training course a year. These usually started (5) a Sunday evening and lasted six days.

Once I was (6) a week’s training course with about forty (7) sales people. I was in the bar on the Friday evening and suddenly a woman who was (8) behind the bar asked mea curious question. "I hope you don’t (9) my asking," she said, "but I’ve been (10) about it all week. Have you got a sister (11) Mary" The woman’s name was June. And she used to do various jobs at the training centre. She worked in the office, she organized all the food and drink for the centre and she worked in the bar at lunchtime and in the evening.

My answer (12) June’s question was "Yes", and June said, "I thought (13) . I met her last September when she was organizing a course here. " At that time, my sister was working for (14) company but in a different part of the country. That was (15) she came to be at the training centre.

(16) surprised me was how June guessed we were brother and sister. Three things made it even more (17) . First, she had met my sister six months before she met me. Second, they have about sixty new people every week at the training centre. So about one thousand five hundred people had (18) the centre in those six months. And (19) , my sister is married, so she doesn’t have the same family name as me.

We’re not (20) , but I guess we must look quite like each other.

12().

A.of

B.about

C.to

D.for

题型:填空题

与传统化油器发动机相比,装有电控燃油喷射系统的发动机功率提高了()。

A.5%~10%

B.10%~15%

C.15%~20%

D.20%

题型:填空题

变压器充电时前应检查电源电压,使充电的变压器各侧电压不超过相应分接点电压的().

A、5%

B、10%

C、15%

D、20%

更多题库