东莞市翰林实验学校九年级上学期第一次月考
翰林外国语学校九年级物理第一次月考试卷

翰林外国语学校九年级物理第一次月考试卷姓名总分一转眼,已是初三年级的学生了,我们已获取了许多新的物理知识,提高了多方面的认知能力,现在是展示你实力的时候,你可要尽情地发挥哦!祝你成功!一、单项选择题(本题16小题,每小题3分,共48分。
在每小题列出的四个选项中,只有一项是正确的,请将正确选项的字母写在答题卡内)1、登月宇航员从月球带回一块矿石,这块矿石不变的是()A.质量B.重力C.温度D.位置2、能比较方便地用来表示银河系大小的长度单位是:()A、光年B、mC、nmD、km3、明代诗人曾写下这样一首诗:“空手把锄头,步行骑水牛,人在桥上走,桥流水不流”其中“桥流水不流”之句应理解成其选择的参照物是:()A.水 B.桥 C.人 D.地面4、.甲、乙两立方体的边长之比是2∶1,质量之比是4∶3,那么甲、乙两物体的密度之比是()A.3∶8B.4∶6C.1∶6D.2∶35、感受你身边的物理———质量为1.5×10-2㎏的物体可能是 ( )A、钢笔 B、课桌 C、电脑D、铅球6、100 g水全部变成冰后,则()A.质量变小,密度也变小B.质量不变,密度也不变C.质量变小,密度不变D.质量不变,密度变小7、用托盘天平测一小铁块的质量,在测量过程中,发现平衡指针稍微偏右,下列操作中正确的是:()A、向左调横梁平衡螺母B、向右调横梁平衡螺母C、向左移动游码D、向右移动游码8、下面有关误差问题的说法中正确的是 ( )A、实验中产生的错误,叫误差B、误差是由于测量时不遵守操作规则而引起的C、认真测量可以避免误差D、多次测量取平均值的办法,可以减小误差9、关于物体的质量和物质的密度,下列说法中正确的是()A.一块冰全部溶化成水后,质量变小,密度不变B.把铜块碾成铜片,质量和密度均不变C.宇航员在太空处于失重状态,故质量和密度均为零D.把铁球加热,质量变大,密度变小10、寓言《龟兔赛跑》中说,兔子在和乌龟赛跑的过程中,因为骄傲睡起了大觉,当它醒来时,乌龟已经爬到了终点。
广东省东莞市翰林中学2019-2020学年九年Word版级上学期月考考试英语试题(Word版含答案)

翰林九年级上学期开学考试英语试卷测试时间:60分钟,满分120分一.单项填空(每小题2分,25道小题,共50分)1. I want to buy ______underwear.A. anB. aC. theD. /2. I was_____ tired____ I didn’t want to do anything.A. too, toB. so, thatC. very, thatD. enough, to3. Tom was watching TV _____ someone knocked at the door.A. whenB. whileC. beforeD. after4. He ____ on the farm while the UFO ____ above him.A. is working, flewB. worked, flewC. works, was flyingD. was working, was flying5.---- I feel a little hungry.---- Why not _____ for dinner with us?A. goB. to goC. you goD. do you go6.They always talk ______ doing homework.A. insteadB. instead aboutC. instead toD. instead of7. You should get up early ____ you can catch the early bus.A. untilB. so thatC. unlessD. in orter to8. ______ newspapers every morning is her habit.A. Looking upB. Looking forC. Looking overD. Looking through9. He can’t turn himself into a person_____ he can hide his tail.A. afterB. whenC. unlessD. as soon as10. They always compare me _______other children.A. aboutB. forC. withD. to11. The alarm didn’t _____ so I woke up late.A. go upB. go outC. go awayD. go off12. _____ water, turn it off after you take a shower.A. SaveB. To saveC. SavingD. Saved13. The train will _____ soon.A. arriveB. get toC. reachD. arrive in14. This song reminded me _____ my childhood.A. ofB. toC. aboutD. for15.------Linda, I called you this morning, but nobody answered the phone.------I’m sorry. I _______ football with my friends then.A. playB. playedC. am playingD. was playing16. ------Dad, why should I stop_____ computer games?------- For your health, my boy.A. to playB. playingC. playD. played17. He______ until the meeting is over.A. leavesB. will leaveC. won’t leaveD. didn’t leave18.-----We have five kinds of bags. Do you like this one ?------ No. Can you show me ______?A. otherB. anotherC. the otherD. others19. _____he is only three years old, he can write many words.A. AlthoughB. IfC. SoD. But20. -----I lost my schoolbag yesterday.------_____________.A. You are welcome.B. Good luck.C. I’m sorry to hear that.D. It doesn’t matter.21. It’s too hot in the room. Would you mind ___________ the air-conditioner?A.to turn onB. turning offC. turn offD. turning on22. --- Could you please clean the room?--- _________. I have to finish my homework.A. It doesn’t matter.B. With pleasureC. You’re welcomeD. Sorry, I can’t23. John was _________shocked ____________ he couldn’t say a word after hearing the news.A. too, toB. very, toC. so, thatD. not, until24. I didn’t go to bed last night ___________ my mother came back.A. afterB. ifC. beforeD. until25. ___________ the boy is ten years old, __________ he can speak five languages.A. Although, /B. Although, butC. Although, soD. Although, and二.完形填空(每小题2分,10小题,共20分)Grandma Sally is eighty-six years old.She has no sons26daughters.Her husband died ten years ago.But she didn’t move into a nursing home.She would like to 27herself every day.Every night she spends two hours28kids with math.All kids living on her street can get her help without payment(报酬).She was a famous math 29before she retired(退休) from a middle school.She gets up early in the morning,then does sports,goes shopping or helps cleaners30the street.And she does these happily.When the kids come for help,she is always31and tries her best.People asked her32.She said,“I love it.It makes me happy to help them.”She is always happy every day and always says hello to people around her33 a smile.“ I 34to love everything around me.So I’m happy to do something.I’m thankful for those kids who come to me for help.Each kid is my 35.I love each day to help them,” she said.26.A.and B.or C.but D.so27.A.look like B.look at C.look after D.look for28.A.helping B.working C.studying D.teaching29.A.teacher B.nurse C.worker D.cleaner30.A.do B.run C.sweep D.play31.A.awful B.happy C.tired D.boring32.A.why B.where C.when D.how33.A.for B.on C.in D.with34.A.have decided B.decides C.haven’t decided D.hate35.A.example B.gift C.teacher D .helper三.阅读理解(每小题2分,15道小题,共30分)AThe best way of learning a language is using it. The best way of learning English is talking in English as much as possible. Sometimes you will get your words mixed up and people will not understand you. Sometimes people will say things too quickly and you can’t understand them. If you keep your sense of humor , you can always have a good laugh at the mistakes you make.Don’t be unhappy if people seem to be laughing at your mistakes. It’s better for people to laugh at your mistakes than to be an gry with you, because they don’t understand what you are saying. The mos t important thing for learning English is: “Don’t be afraid of making mistakes because everyone makes mistakes.”36. The writer thinks that the best way for you to learn a language is _____________.A. writingB. using itC. listeningD. learning grammar37. What should you do in learning English?A. Be careful not to make any mistake.B. Write as quickly as you can.C. Speak English as much as you can.D. Laugh more often.38. When people laugh at your mistakes, you should _________.A. not careB. be angryC. feel worriedD. be unhappy39. When you make a mistake, you should__________.A. keep quietB. get angryC. be kindD. keep your sense of humor40. The story tells us:__________.A. Only foolish(愚蠢的) people make mistakesB. Few people make mistakesC. People never make mistakesD. There is no one who doesn’t make mistakesBSixtee n years ago a boy gave me an important gift.It was a smile.It was the early autumn of my first year at a middle school,and my old school was far away.As a result,no one knew who I was.I was very lonely,and afraid to speak to anyone.Every time I heard the other students talking and laughing,I felt my heart break.I couldn’t talk with anyone about my problems.Then one day,when my classmates were talking happily with their friends,I was sitting at my desk unhappily as usual.At that moment,a boy entered the classroom.I didn’t know who he was.He passed by me and then turned back.He looked at me,with a smile.Suddenly,I felt the touch of something bright and friendly.It made me feel happy and warm.That smile changed my life.I started to talk with other students and make friends.Day by day,I became closer to everyone in my class.The boy with the lucky smile has become my best friend.One day I asked him why he had smiled,but he couldn’t remember doing so!It doesn’t matter because all the dark days have gone.I believe that the world is what you think it is.If you think itis lonely,you might always be alone.So smile at the world and it will smile back.41.When did the writer get the gift?A.At the age of 16.B.After making friends with the boy.C.In the first year at a middle school.D.After becoming closer to everyone in the class.42.Why was the smile an important gift?A.Because the writer’s old school was far away.B.Because the writer didn’t know who the boy was.C.Because the smile didn’t mean anything to the boy.D.Because the writer felt lonely and had no friends and it made her feel happy and warm.43.Why didn’t the writer talk to anyone in her new school about her problems?A.Because she was always unhappy.B.Because she didn’t know anyone at that time.C.Because she was in the first year at the junior high school.D.Because she didn’t want her parents to worry about her.44.How did the smile change her life?A.She started to make friendsB.She became the best friend of the boy.C.Her parents didn’t worry about her any more.D.She realized that she was lonely.45.Where does she now think her feeling of unhappiness came from?A.From her old school.B.From her parents.C.From herself.D.From her classmates at the new school.C配对阅读。
东莞市-九年级上第一次月考数学试卷含答案解析.doc

2016-2017学年广东省东莞市旭东学校九年级(上)第一次月考数学试卷一、选择题1.下列方程是一元二次方程的是()A.ax2+bx+c=0 B.x2+2x=x2﹣1 C.(x﹣1)(x﹣3)=0 D.=2 2.下列函数中,开口方向向上的是()A.y=ax2B.y=﹣2x2C.D.3.抛物线y=2x2﹣3的顶点在()A.第一象限B.第二象限C.x轴上D.y轴上4.用配方法解一元二次方程x2+8x+7=0,则方程可化为()A.(x+4)2=9 B.(x﹣4)2=9 C.(x+8)2=23 D.(x﹣8)2=9 5.方程ax2+bx+c=0(a≠0)有实数根,那么成立的式子是()A.b2﹣4ac>0 B.b2﹣4ac<0 C.b2﹣4ac≤0 D.b2﹣4ac≥0 6.关于x的一元二次方程x2+4x+k=0有两个相等的实根,则k的值为()A.k=﹣4 B.k=4 C.k≥﹣4 D.k≥47.下列方程中两实数根互为倒数有()①x2﹣2x﹣1=0;②2x2﹣7x+2=0;③x2﹣x+1=0.A.0个B.1个C.2个D.3个8.在一次篮球联赛中,每个小组的各队都要与同组的其他队比赛两场,然后决定小组出线的球队.如果某一小组共有x个队,该小组共赛了90场,那么列出正确的方程是()A.B.x(x﹣1)=90 C.D.x(x+1)=90 9.在同一直角坐标系中,一次函数y=ax+c和二次函数y=ax2+c的图象大致为()A .B .C .D .10.已知a ,b 为实数,(a 2+b 2)2﹣(a 2+b 2)﹣6=0,则代数式a 2+b 2的值为( ) A .2 B .3 C .﹣2 D .3或﹣2 二、填空题11.方程3x 2=x 的解为 .12.已知方程x 2+kx ﹣2=0的一个根是1,则另一个根是 ,k 的值是 .13.写出一个以﹣3和2为根的一元二次方程: .14.某商品原价289元,经连续两次降价后售价为256元,设平均每次降价的百分率为x ,那么根据题意可列关于x 的方程是 .15.关于x 的一元二次方程(m ﹣1)x 2+x +m 2﹣1=0有一根为0,则m= .三、解答题 16.按要求解方程(1)x 2﹣4x +1=0(配方法) (2)4x 2﹣6x ﹣3=0(运用公式法)(3)(2x ﹣3)2=5(2x ﹣3)(分解因式法) (4)(x +8)(x +1)=﹣12(运用适当的方法)17.求证:方程2x 2+3(m ﹣1)x +m 2﹣4m ﹣7=0对于任何实数m ,永远有两个不相等的实数根.18.阅读下面的例题,解方程(x ﹣1)2﹣5|x ﹣1|﹣6=0例:解方程x 2﹣|x |﹣2=0;解:令y=|x |,原方程化成y 2﹣y ﹣2=0解得:y 1=2,y 2=﹣1当|x |=2,x=±2;当|x |=﹣1时(不合题意,舍去)∴原方程的解是x 1=2,x 2=﹣2.19.如图,要利用一面墙(墙长为25米)建羊圈,用100米的围栏围成总面积为400平方米的三个大小相同的矩形羊圈,求羊圈的边长AB,BC各为多少米?20.为进一步发展基础教育,自2014年以来,某县加大了教育经费的投入,2014年该县投入教育经费6000万元.2016年投入教育经费8640万元.假设该县这两年投入教育经费的年平均增长率相同.(1)求这两年该县投入教育经费的年平均增长率;(2)若该县教育经费的投入还将保持相同的年平均增长率,请你预算2017年该县投入教育经费多少万元.21.关于x的一元二次方程(a﹣6)x2﹣8x+9=0有实根.(1)求a的最大整数值;(2)当a取最大整数值时,①求出该方程的根;②求的值.2016-2017学年广东省东莞市旭东学校九年级(上)第一次月考数学试卷参考答案与试题解析一、选择题1.下列方程是一元二次方程的是()A.ax2+bx+c=0 B.x2+2x=x2﹣1 C.(x﹣1)(x﹣3)=0 D.=2 【考点】一元二次方程的定义.【分析】根据一元二次方程的定义分别判断即可.【解答】解:A、没有说明a是否为0,所以不一定是一元二次方程;B、移项合并同类项后未知数的最高次为1,所以不是一元二次方程;C、方程可整理为x2﹣4x+3=0,所以是一元二次方程;D、不是整式方程,所以不是一元二次方程;故选:C.【点评】本题主要考查一元二次方程的定义,注意有的方程需要整理成一元二次方程的一般形式后再进行判断.2.下列函数中,开口方向向上的是()A.y=ax2B.y=﹣2x2C.D.【考点】二次函数的性质.【分析】当二次函数的中二次项的系数大于0时,其开口向下,可求得答案.【解答】解:在y=ax2中,当a>0时,抛物线开口向上,在y=x2中,a=>0,∴其开口向上,故选C.【点评】本题主要考查二次函数的性质,掌握二次函数的中二次项系数的正负决定抛物线的开口方向是解题的关键.3.抛物线y=2x2﹣3的顶点在()A.第一象限B.第二象限C.x轴上D.y轴上【考点】二次函数的性质.【分析】已知抛物线解析式为顶点式,根据顶点坐标的特点,直接写出顶点坐标,再判断顶点位置.【解答】解:由y=2x2﹣3得:抛物线的顶点坐标为(0,﹣3),∴抛物线y=2x2﹣3的顶点在y轴上,故选D.【点评】主要考查了求抛物线的顶点坐标与对称轴的方法.4.用配方法解一元二次方程x2+8x+7=0,则方程可化为()A.(x+4)2=9 B.(x﹣4)2=9 C.(x+8)2=23 D.(x﹣8)2=9【考点】解一元二次方程-配方法.【分析】将常数项移动方程右边,方程两边都加上16,左边化为完全平方式,右边合并即可得到结果.【解答】解:x2+8x+7=0,移项得:x2+8x=﹣7,配方得:x2+8x+16=9,即(x+4)2=9.故选A【点评】此题考查了解一元二次方程﹣配方法,利用此方法解方程时,首先将二次项系数化为1,常数项移动方程右边,然后左右两边都加上一次项系数一半的平方,左边化为完全平方式,右边合并为一个非负常数,开方转化为两个一元一次方程来求解.5.方程ax2+bx+c=0(a≠0)有实数根,那么成立的式子是()A.b2﹣4ac>0 B.b2﹣4ac<0 C.b2﹣4ac≤0 D.b2﹣4ac≥0【考点】根的判别式.【分析】直接根据判别式的意义判断.【解答】解:根据题意得△=b2﹣4ac≥0.故选D.【点评】本题考查了一元二次方程ax2+bx+c=0(a≠0)的根的判别式△=b2﹣4ac:当△>0,方程有两个不相等的实数根;当△=0,方程有两个相等的实数根;当△<0,方程没有实数根.6.关于x的一元二次方程x2+4x+k=0有两个相等的实根,则k的值为()A.k=﹣4 B.k=4 C.k≥﹣4 D.k≥4【考点】根的判别式.【分析】根据判别式的意义得到△=42﹣4k=0,然后解一次方程即可.【解答】解:∵一元二次方程x2+4x+k=0有两个相等的实根,∴△=42﹣4k=0,解得:k=4,故选:B.【点评】本题考查了一元二次方程ax2+bx+c=0(a≠0)的根的判别式△=b2﹣4ac:当△>0,方程有两个不相等的实数根;当△=0,方程有两个相等的实数根;当△<0,方程没有实数根.7.下列方程中两实数根互为倒数有()①x2﹣2x﹣1=0;②2x2﹣7x+2=0;③x2﹣x+1=0.A.0个B.1个C.2个D.3个【考点】根与系数的关系.【分析】两根互为倒数就是两根之积为1,从而求解.【解答】解:设方程的两根为a,b,①ab=﹣1,不合题意;②ab==1,符合题意;③b2﹣4ac=1﹣4<0,没有实数根,所以不符合题意.故选B.【点评】考查了根与系数的关系,解题的关键是了解两根之积等于多少,难度一般.8.在一次篮球联赛中,每个小组的各队都要与同组的其他队比赛两场,然后决定小组出线的球队.如果某一小组共有x个队,该小组共赛了90场,那么列出正确的方程是()A.B.x(x﹣1)=90 C.D.x(x+1)=90 【考点】由实际问题抽象出一元二次方程.【分析】如果设某一小组共有x个队,那么每个队要比赛的场数为(x﹣1)场,有x个小队,那么共赛的场数可表示为x(x﹣1)=90.【解答】解:设某一小组共有x个队,那么每个队要比赛的场数为x﹣1;则共赛的场数可表示为x(x﹣1)=90.故本题选B.【点评】本题要注意比赛时是两支队伍同时参赛,且“每个小组的各队都要与同组的其他队比赛两场”,以免出错.9.在同一直角坐标系中,一次函数y=ax+c和二次函数y=ax2+c的图象大致为()A.B.C.D.【考点】二次函数的图象;一次函数的图象.【分析】根据二次函数的开口方向,与y轴的交点;一次函数经过的象限,与y轴的交点可得相关图象.【解答】解:∵一次函数和二次函数都经过y轴上的(0,c),∴两个函数图象交于y轴上的同一点,故B选项错误;当a>0时,二次函数开口向上,一次函数经过一、三象限,故C选项错误;当a<0时,二次函数开口向下,一次函数经过二、四象限,故A选项错误;故选:D.【点评】本题考查二次函数及一次函数的图象的性质;用到的知识点为:二次函数和一次函数的常数项是图象与y轴交点的纵坐标;一次函数的一次项系数大于0,图象经过一、三象限;小于0,经过二、四象限;二次函数的二次项系数大于0,图象开口向上;二次项系数小于0,图象开口向下.10.已知a,b为实数,(a2+b2)2﹣(a2+b2)﹣6=0,则代数式a2+b2的值为()A.2 B.3 C.﹣2 D.3或﹣2【考点】换元法解一元二次方程.【分析】设a2+b2=x,将原方程变形,解一元二次方程即可.【解答】解:设a2+b2=x,原方程变形为,x2﹣x﹣6=0,解得x=3或﹣2,∵a2+b2≥0,∴a2+b2=3,故选B.【点评】本题考查了用换元法解一元二次方程,解题的关键是找出要变形的整体.二、填空题11.方程3x2=x的解为x1=0,x2=.【考点】解一元二次方程-因式分解法.【分析】可先移项,然后运用因式分解法求解.【解答】解:原方程可化为:3x2﹣x=0,x(3x﹣1)=0,x=0或3x﹣1=0,解得:x1=0,x2=.【点评】本题考查了解一元二次方程的方法,当把方程通过移项把等式的右边化为0后方程的左边能因式分解时,一般情况下是把左边的式子因式分解,再利用积为0的特点解出方程的根.因式分解法是解一元二次方程的一种简便方法,要会灵活运用.12.已知方程x2+kx﹣2=0的一个根是1,则另一个根是﹣2,k的值是1.【考点】根与系数的关系.【分析】可将该方程的已知根1代入两根之积公式和两根之和公式列出方程组,解方程组即可求出k值和方程的另一根.【解答】解:设方程的也另一根为x1,又∵x=1,∴,解得x1=﹣2,k=1.【点评】此题也可先将x=1代入方程x2+kx﹣2=0中求出k的值,再利用根与系数的关系求方程的另一根.13.写出一个以﹣3和2为根的一元二次方程:x2﹣x﹣6=0.【考点】根与系数的关系.【分析】本题根据一元二次方程的根的定义,一根为3,另一个根为﹣2,则方程是(x﹣3)(x+2)=0的形式,即可得出答案.【解答】解:根据一个根为x=3,另一个根为x=﹣2的一元二次方程是:x2﹣x﹣6=0;故答案为:x2﹣x﹣6=0.【点评】此题考查了根与系数的关系,已知方程的两根,写出方程的方法是需要熟练掌握的一种基本题型.14.某商品原价289元,经连续两次降价后售价为256元,设平均每次降价的百分率为x,那么根据题意可列关于x的方程是289(1﹣x)2=256.【考点】由实际问题抽象出一元二次方程.【分析】增长率问题,一般用增长后的量=增长前的量×(1+增长率),本题可参照增长率问题进行计算,如果设平均每次降价的百分率为x,可以用x表示两次降价后的售价,然后根据已知条件列出方程.【解答】解:根据题意可得两次降价后售价为289(1﹣x)2,即方程为289(1﹣x)2=256.故答案为:289(1﹣x)2=256.【点评】本题考查一元二次方程的应用,解决此类两次变化问题,可利用公式a(1+x)2=c,其中a是变化前的原始量,c是两次变化后的量,x表示平均每次的增长率.15.关于x的一元二次方程(m﹣1)x2+x+m2﹣1=0有一根为0,则m=﹣1.【考点】一元二次方程的解.【分析】根据一元二次方程的解的定义,将x=0代入原方程,列出关于m的方程,通过解关于m的方程即可求得m的值.【解答】解:∵关于x的一元二次方程(m﹣1)x2+x+m2﹣1=0有一根为0,∴x=0满足关于x的一元二次方程(m﹣1)x2+x+m2﹣1=0,且m﹣1≠0,∴m2﹣1=0,即(m﹣1)(m+1)=0且m﹣1≠0,∴m+1=0,解得,m=﹣1;故答案是:﹣1.【点评】本题考查了一元二次方程的解.注意一元二次方程的二次项系数不为零.三、解答题16.按要求解方程(1)x2﹣4x+1=0(配方法)(2)4x2﹣6x﹣3=0(运用公式法)(3)(2x﹣3)2=5(2x﹣3)(分解因式法)(4)(x+8)(x+1)=﹣12(运用适当的方法)【考点】解一元二次方程-因式分解法;解一元二次方程-配方法;解一元二次方程-公式法.【分析】根据一元二次方程的解法即可求解.【解答】解:(1)x2﹣4x+4=4﹣1,∴(x﹣2)2=3,∴x=2±;(2)∵a=4,b=﹣6,c=﹣3,∴△=b2﹣4ac=(﹣6)2﹣4×4×(﹣3)=36+48=84,∴x==;(3)(2x﹣3)2﹣5(2x﹣3)=0,∴(2x﹣3)(2x﹣3﹣5)=0,∴x=或x=4;(4)x2+9x+8=﹣12,∴x2+9x+20=0,∴(x﹣4)(x﹣5)=0,x=4或x=5【点评】本题考查一元二次方程的解法,属于基础题型.17.求证:方程2x2+3(m﹣1)x+m2﹣4m﹣7=0对于任何实数m,永远有两个不相等的实数根.【考点】根的判别式.【分析】先计算△=9(m﹣1)2﹣4×2(m2﹣4m﹣7)=m2+14m+65=(m+7)2+16,由(m+7)2≥0得到△>0,即可证明原方程有两个不相等的实数根.【解答】解:△=9(m﹣1)2﹣4×2(m2﹣4m﹣7),=m2+14m+65,=(m+7)2+16.∵对于任何实数m,(m+7)2≥0,∴△>0,即原方程有两个不相等的实数根.所以方程2x2+3(m﹣1)x+m2﹣4m﹣7=0对于任何实数m,永远有两个不相等的实数根.【点评】本题考查了一元二次方程ax2+bx+c=0(a≠0,a,b,c为常数)根的判别式.当△>0,方程有两个不相等的实数根;当△=0,方程有两个相等的实数根;当△<0,方程没有实数根.18.阅读下面的例题,解方程(x﹣1)2﹣5|x﹣1|﹣6=0例:解方程x2﹣|x|﹣2=0;解:令y=|x|,原方程化成y2﹣y﹣2=0解得:y1=2,y2=﹣1当|x|=2,x=±2;当|x|=﹣1时(不合题意,舍去)∴原方程的解是x1=2,x2=﹣2.【考点】解一元二次方程-因式分解法.【分析】仿照例题依次计算即可.【解答】解:令y=|x﹣1|,原方程可化为:y2﹣5y﹣6=0,解得:y=﹣1或y=6,当|x﹣1|=﹣1时,不符合题意,舍去;当|x﹣1|=6时,即x﹣1=6或x﹣1=﹣6,解得:x=7或x=﹣5.【点评】本题主要考查解方程的能力,理解题意是解题的根本,掌握因式分解法解方程的能力是关键.19.如图,要利用一面墙(墙长为25米)建羊圈,用100米的围栏围成总面积为400平方米的三个大小相同的矩形羊圈,求羊圈的边长AB,BC各为多少米?【考点】一元二次方程的应用.【分析】设AB的长度为x米,则BC的长度为(100﹣4x)米;然后根据矩形的面积公式列出方程.【解答】解:设AB的长度为x米,则BC的长度为(100﹣4x)米.根据题意得(100﹣4x)x=400,解得x1=20,x2=5.则100﹣4x=20或100﹣4x=80.∵80>25,∴x2=5舍去.即AB=20,BC=20.答:羊圈的边长AB,BC分别是20米、20米.【点评】本题考查了一元二次方程的应用.解题关键是要读懂题目的意思,根据题目给出的条件,找出合适的等量关系,列出方程,再求解.20.为进一步发展基础教育,自2014年以来,某县加大了教育经费的投入,2014年该县投入教育经费6000万元.2016年投入教育经费8640万元.假设该县这两年投入教育经费的年平均增长率相同.(1)求这两年该县投入教育经费的年平均增长率;(2)若该县教育经费的投入还将保持相同的年平均增长率,请你预算2017年该县投入教育经费多少万元.【考点】一元二次方程的应用.【分析】(1)设该县投入教育经费的年平均增长率为x,根据2014年该县投入教育经费6000万元和2016年投入教育经费8640万元列出方程,再求解即可;(2)根据2016年该县投入教育经费和每年的增长率,直接得出2017年该县投入教育经费为8640×(1+0.2),再进行计算即可.【解答】解:(1)设该县投入教育经费的年平均增长率为x,根据题意得:6000(1+x)2=8640解得:x1=0.2=20%,x2=﹣2.2(不合题意,舍去),答:该县投入教育经费的年平均增长率为20%;(2)因为2016年该县投入教育经费为8640万元,且增长率为20%,所以2017年该县投入教育经费为:y=8640×(1+0.2)=10368(万元),答:预算2017年该县投入教育经费10368万元.【点评】此题考查了一元二次方程的应用,掌握增长率问题是本题的关键,若设变化前的量为a,变化后的量为b,平均变化率为x,则经过两次变化后的数量关系为a(1±x)2=b.21.关于x的一元二次方程(a﹣6)x2﹣8x+9=0有实根.(1)求a的最大整数值;(2)当a取最大整数值时,①求出该方程的根;②求的值.【考点】根的判别式;解一元二次方程-公式法.【分析】(1)根据一元二次方程的定义和根的判别式得到△=64﹣4×(a﹣6)×9≥0且a﹣6≠0,解得a≤且a≠6,然后在次范围内找出最大的整数;(2)①把a的值代入方程得到x2﹣8x+9=0,然后利用求根公式法求解;②由于x2﹣8x+9=0则x2﹣8x=﹣9,然后把x2﹣8x=﹣9整体代入所求的代数式中得到原式=2x2﹣=2x2﹣16x+,再变形得到2(x2﹣8x)+,再利用整体思想计算即可.【解答】解:(1)根据题意△=64﹣4×(a﹣6)×9≥0且a﹣6≠0,解得a≤且a≠6,所以a的最大整数值为7;(2)①当a=7时,原方程变形为x2﹣8x+9=0,△=64﹣4×9=28,∴x=,∴x1=4+,x2=4﹣;②∵x2﹣8x+9=0,∴x2﹣8x=﹣9,所以原式=2x2﹣,=2x2﹣16x+,=2(x2﹣8x)+,=2×(﹣9)+,=﹣.【点评】本题考查了一元二次方程ax2+bx+c=0(a≠0)的根的判别式△=b2﹣4ac:当△>0,方程有两个不相等的实数根;当△=0,方程有两个相等的实数根;当△<0,方程没有实数根.也考查了一元二次方程的定义和解法以及整体思想.。
2018-2019 上学期东莞翰林第一次月考初三英语试题

2018-2019 上学期东莞翰林第一次月考初三英语试题一、单项填空(本大题有20 小题,每小题 1 分,共20 分)()1. Tom sang as Jim. So they got the same score in the competition.A. as well asB. not as well asC. better thanD. worse than ()2. --Shall we go and see the film Furious7?.--I’d love to, but I it twice.A. have seenB. seeC.sawD.was seeing ()3. Tom will come back for his passport two days.A. onB. afterC. behindD.in()4. Tom was brave. He jumped into the river to save 8-year-old boy just now.A. aB. anC. theD. / ()5. If youstick to your dream, I’m sure you can make come true.A. your;itB. your;themC. yours;itD. yours;the ()6.Nick, itis the time in two days that you have made the same mistake.A.twoB. secondC. oneD. first ()7.We will go hiking next Sunday it rains hard.A. untilB. unlessC. as soon asD. when ()8. --Ma Long won his first World Table Tennis Championship in Suzhou in 2015.-- exciting news!A. HowB. WhatC. What aD. What an ()9. --Ireally wanted to know--I went there by train..A. What were you doing last nightB. How you went there last nightC. When you arrived thereD. Who would go with you ()10. The boyhas studied in this school since he here.A. comesB.cameC. has comeD. will come ()11. --Is your toothache getting better, Lucy?--No, it is even . I have to see the dentist again.A. badB. worseC. goodD. better ()12. --Would you please show me how to use Wechat with others?--At anytime you like when I am on line.A. talkB. to talkC. talkingD. to talking ()13. Annie isa humorous girl everyone likes talkingA. too; toB. so; thatC. such;thatD. very; that ()14. Even though my grandma lives , she never feels .A. lonely; aloneB. alone; lonelyC. lonely;lonelyD. alone; alone ()15. My mom is ill in bed. I have to take care of .A. herB. herselfC. hersD. she()16. --Are the Smiths living in the house alone?--Yes, although they have three sons, of them lives with their parents.A. neitherB. bothC. allD.none( )17. The accident happened the old mana cold morning.A. to; toB. in;inC. in;toD. to;on( )18.—Could you tell me ?—He to Australia.A. where is he; has goneB. where he is; has beenC. Where he is; has goneD. where is he; has been( )19. --How long you the book?--For only a week..A. have; borrowedB. did; lendC. have;keptD. did; have()20. --Would you mind looking after my dog while I am on holiday?-- .A. Of course notB. Yes, I’d be happy toC. Not at all, I’ve no timeD. Yes, please二、完形填空(本大题有10 小题,每小题 1.5 分,共15 分)Every day, on her way to work, Amelia had to pass a slum(贫民窟). As a social worker, she had not paid much21 to it. This changed one day when she met a ragged(衣衫褴褛的) 22 named Sam. Sam knew she was the head of social services, and that she could help. He reached out his 23 and said, “Can you help me? I’m 24 for my dad.” His hands were so cold. Amelia said, “What’s up?” “My mom is 25 sick. Her birthday is coming. I know my father’s coming back would be the best 26 . My dad had left us before I was two years old,” said the boy.Amelia was deeply 27 and asked Sam to take her to his home. Amelia saw a woman lying on the bed. The woman knew she was 28 . She said to Amelia, “Please find a home for my son.”Amelia took her hand and nodded 29 tears. She got an idea! Her husband and she had no children. Amelia brought Sam home. 30 made up a happy family()21. A. attention()22. A. friendB. decisionB. neighborC. moneyC. girlD. timeD.boy()23. A. finger B. hand C. leg D. foot()24. A. looking up B. Looking over C. looking for D. Looking after()25. A. especially B. terribly C. happily D. hardly()26. A. present B. festival C. condition D. celebration()27. A. surprised B. interested C. pleased D. moved()28. A. leaving B. sleeping C. dying D.dreaming()29. A. for B. with C. over D. through()30. A. it B. she C. he D. they三、阅读理解(本大题有 15 小题,每小题 2 分,共 30 分)A Next Month'sBig EventsEvery year on May 5, if you walk along the street in Japan, you'll see colorful carp flags (鲤鱼旗) outside people's houses.They are there to celebrate Boys' Day, a traditional Japanese festival. The flags show parents' best wishes for their sons.They are symbols of strong and healthy boys.JJ Lam comes to BeijingIf you want to watch a good concert and learn something at the same time, you could go to JJ Lam's Timeline: Genesis WorldTour. The 34-year-old Singaporean star will perform in Beijing on May 9. Fans outside Beijing shouldn't be disappointed.Lam's tour will go to other cities in China including Jinan, Xi'an and Wuhan in the following months.Mother's DayIt is a good opportunity for you to do something nice for your mom. It falls onthe second Sunday in May, so this year it's on May 8. People in more than 40 countries celebrate Mother's Day each year.In the US, the fathers and children cook and serve breakfast for the mothers in bed.People also buy their mothers carnations (康乃馨 ) which stand for happiness and love.Cheese rolling eventWelcome to Cooper's Hill Cheese Rolling and Wake in England ! The tradition is held every year on the last Monday in May. This year the event falls on May 27.On that day, groups of fearless racers will get together to chase an 8 pound (3.5kg) cheese down Cooper's Hill. They do it to take home the cheese. If you're the first one down the hill, you win it.()31.According to the information above, this month is .A. March B. April C. May D. June ()32.JJ Lam's concert in Beijing is on.A. May5B. May 8C. May 9D. May 27 ()33.Cheese rolling event takes place in .A. JapanB. ChinaC. the USD. theUK ()34.Which of the following is true ?A.Carp flags are symbols of strong and healthy children in Japan.B.J J Lam's fans are very disappointed at his concert this year.C.Carnations are the flowers for mothers on Mother's day.D.The person who reaches the top of the hill wins the cheese. ()35.You might read the information above in . A. a newspaper B. a textbook C. a story book D. a science magazineBWe know the mosquito very well. Mosquitoes fly everywhere.They can be found almost all over the world,and there are more than 2 500 kinds of them.No one likes the mosquito.But the mosquito may decide that she loves you.She?Yes,she.It's true that male mosquito doesn't bite( 咬 ) and only the female mosquito bites because she needs blood to lay eggs.She is always looking for things or people she wants to bite.If she likes what she finds,she bites.But if she doesn't like your blood,shewill turn to someone else for more delicious blood.Next time a mosquito bites you,just remember you are chosen.You're different from the others!If the mosquito likes you,she lands on your body without letting you know.She bites you so quickly and quietly that you may not feel anything different.After she bites,you will have an itch(痒) on your body because she puts something from her mouth together with your blood.By the time the itching begins,she has flown away.And then what happens?Well,after her delicious dinner,the mosquito feels tired.She just wants to find a place to have a good rest.There,on a leaf or a wall,she begins to lay eggs,hundreds of eggs .()36. "Mosquito" means in Chinese.A. 苍蝇 B. 蜻蜓 C. 跳蚤 D. 蚊子()37. There are more than kinds of mosquitoes in the world..A. 25B. 250C. 2,500D. 2,500,000()38. If the mosquito doesn’t bite you, it will .A. get angry with youB. be afraid of youC. make a lot of noiseD. choose another one ()39. The mosquito bites you .A. when you’re asleepB. because you have choose itC. too quickly to let you knowD. but doesn’t like you ()40. Which of the following sentences is wrong?A.Male mosquito doesn’t bite..B.Mosquitoes use blood to lay eggsC.The itching begins after the mosquito bites you..D.All the mosquitoes don’t like to bite people for blood.C配对阅读左栏是对五个人物的描述,右栏是广告的简介,请为左栏的每位学生选择一个合适的广告。
东莞市九年级上学期物理第一次月考试卷

东莞市九年级上学期物理第一次月考试卷姓名:________ 班级:________ 成绩:________一、单项选择题(本大题共6小题,每小题3分,共18分) (共6题;共18分)1. (3分) (2019九上·揭西月考) 下列有关分子热运动的说法不正确的是()A . 压紧的铅块能结合在一起,表明分子间有引力B . 墨水在热水中扩散的快,表明温度越高,分子运动越剧烈C . 固体很难被压缩,表明固体分予间只存在斥力D . 桂花飘香,表明分子在不停地做无规则运动2. (3分)如图所示,电梯内一弹簧下挂一物块,当整个电梯突然向上作加速运动时,下列说法正确的是A . 物块速度变大时其惯性增大B . 弹簧对物块的拉力等于物块的重力C . 弹簧对物块的拉力等于物块对弹簧的拉力D . 弹簧伸长了,弹性势能不变3. (3分)(2017·烟台) 如图所示,是汽油机工作时的四个冲程,其中属于做功冲程的是()A .B .C .D .4. (3分) (2015九上·扶沟期中) 在内燃机中,实现了内能向机械能转化的是()A . 吸气冲程B . 压缩冲程C . 做功冲程D . 排气冲程5. (3分)小明家的太阳能热水器内装有100kg、25℃的水,经过一天照射后,温度升高了50℃.则水吸收的热量及至少可以节约煤的质量分别是[如果煤的利用率为50%,水的比热容是4.2×103J/(kg•℃),煤的热值是3.0×107J/kg]()A . 1.05×107J,0.7kgB . 2.1×107J,0.7kgC . 1.05×107J,1.4kgD . 2.1×107J,1.4kg6. (3分)下列估测数据,最接近实际情况的是()A . 初中物理课本的宽度约为185mmB . 人体的安全电压是不高于220VC . 洗澡水的温度大约是60℃D . 新型汽油机的效率可达100%二、填空题(本大题共6小题,每空1分,共19分) (共6题;共15分)7. (2分)进入刚装修完的房屋,我们常常会闻到一种刺鼻的气味,这气味主要来自装修材料中的甲醛这种对人体有害的化学物质.这说明甲醛分子在做________运动.水很难被压缩,说明分子同存在________力.8. (1分) (2018九上·长白期末) 热机的工作原理________,完全燃烧10kg的汽油(热值为4.6×107J/kg),产生的热量为________J。
广东省东莞市翰林实验学校2023-2024学年九年级上学期第一次月考物理试卷(含解析)

2023-2024学年广东省东莞市翰林实验学校九年级(上)月考物理试卷(9月份)一、选择题:(每小题3分,共24分)1.(3分)关于功、功率、机械效率说法正确的是( )A.做功多的机械,功率一定大B.功率大的机械,做功一定快C.做功快的机械,机械效率一定高D.通过改进机械的性能可以使机械效率达到100%2.(3分)如图所示,小明在做模拟“蹦极”的小实验时,将一根橡皮筋一端系一质量为m 的小球,b点是橡皮筋不系小球自然下垂时下端所在的位置,c点是小球从a点自由下落所能到达的最低点,不考虑空气阻力,以下说法正确的是( )A.小球到达b点时速度最大B.小球到达c点时,受的合力为零C.小球的动能一直在增加,重力势能一直在减小D.在c点小球的动能为零,橡皮筋的弹性势能最大3.(3分)如图所示,已知物体A和B质量相等,A在粗糙的水平地面,则F对物体做的功( )A.对A做的功多B.对A和B做的功一样多C.对B做的功多D.条件不足,无法确定4.(3分)如图所示,是采用滑轮组水平向右移动重物的场景。
已知A物体重为20N,在水平面滑动时受到的摩擦力为15N,A物体在10s内匀速移动的距离为0.6m,则( )A .1s 内拉力做的功为3.6JB .滑轮组的机械效率约为83.3%C .拉力F 的功率为1.2WD .绳子自由端移动的速度1.8m/s5.(3分)关于比热容和热值,下列说法正确的( )A .冰熔化成水,它的质量、比热容都不变B .燃料完全燃烧时热值较大,不完全燃烧时热值较小C .一桶汽油用去一半,比热容和热值都不变D .物体热值越大,燃烧时温度越高6.(3分)两个相同的容器分别装满了质量相等的两种液体。
用同一热源分别加热,液体温度与加热时间关系如图( )A .甲液体的比热容大于乙液体的比热容B .如果升高相同的温度,两液体吸收热量相同C .加热相同的时间,甲液体吸收的热量大于乙液体吸收的热量D .加热时间相同,甲液体升高的温度大于乙液体升高的温度7.(3分)把篮球抛向空中,忽略空气阻力,哪一图象能正确反映球离手后至落回地面前机械能(E )(h )的关系( )A .B .C.D.8.(3分)用稳定的热源给一个物体均匀加热,得到它的熔化图象如图所示,那么该物体在固态时的比热容与液态时的比热容之比是( )A.1:2B.1:1C.1:4D.2:1二、选择题:(每空1分,共24分)9.(3分)以下有关“热”的描述,在物理学中的含义各是什么?(选填“内能”、“温度”、“热量”)(1)今天天气真“热”是指 。
广东省东莞市九年级上学期语文第一次月考(开学考试)试卷

广东省东莞市九年级上学期语文第一次月考(开学考试)试卷姓名:________ 班级:________ 成绩:________一、选择题 (共5题;共10分)1. (2分)下列词语中没有错别字的一组是()A . 是非郑重其是矫饰一代天骄B . 喝采五彩缤纷阔绰绰绰有余C . 错失张皇失错具备与日俱增D . 潮汛杳无音讯脉搏博学多才2. (2分)下列划线成语使用不正确的一项是()A . 聪明的资质、内在的干劲和敬业乐群的态度,都是科学研究的必备条件。
B . 小军在辩论会上引经据典,断章取义,博得了观众的阵阵掌声。
C . 开会讨论问题最忌言不及义,而应高效、有针对性商讨,逐一解决问题。
D . 在这个瞬息万变的时代,阅读,特别是深度阅读,是人们保持判断力和思想定力的不二法门。
3. (2分) (2019八下·双鸭山期末) 下列句子有语病的一项是()A . 当众讲话的能力,是演讲水平的一个重要体现。
B . 旅游其实也是一种“阅读”,是认识世界的另一种方式。
C . 憧憬美好的社会生活,反思现实的生存状态,是经典作品中的永恒主题。
D . 北京市55所高校约4000余人参与了北京大学生音乐节开幕式。
4. (2分)(2018·深圳) 请选出下列选项中排序正确的一项()①考察表明,塔里木地区有非常长的聚水期。
②早在30万年前,塔里木盆地和柴达木盆地还是连在一起的大海,后来这里的地壳逐渐抬升。
③这一时期一直持续了数万年,使得塔里木地区积聚了大量地下水。
④但还是个湿润地带,降水比较丰富,草原、沼泽密布。
⑤为什么塔里木盆地地下会形成巨大的地下水库呢?A . ①③②④⑤B . ⑤①②④③C . ⑤②①④③D . ①⑤②④③5. (2分) (2017七下·新余月考) 下列各项中的改句与原句相比,意思发生了明显变化的一项是()A . 原句:他像亲兄弟一样拥抱着这位比他略高的俄国小说家。
改句:他拥抱着这位比他略高而又像亲兄弟一样的俄国小说家。
广东省东莞市九年级上学期数学第一次月考试卷

广东省东莞市九年级上学期数学第一次月考试卷姓名:________ 班级:________ 成绩:________一、单项选择题(每小题2分,共12分) (共6题;共12分)1. (2分)对于抛物线y=(x-5)2+3,下列说法正确的是()A . 开口向下,顶点坐标(5,3)B . 开口向上,顶点坐标(5,3)C . 开口向下,顶点坐标(-5,3)D . 开口向上,顶点坐标(-5,3)2. (2分)二次函数y=x2-2x+3,当函数值为2时,自变量的值是()A . x=-2B . x=2C . x=1D . x=-13. (2分)用配方法解方程x2-2x-5=0时,原方程应变形为()A . (x+1)2=6B . (x+2)2=9C . (x-1)2=6D . (x-2)2=94. (2分) (2017·渠县模拟) 如图,抛物线y=﹣2x2+8x﹣6与x轴交于点A、B,把抛物线在x轴及其上方的部分记作C1 ,将C1向右平移得C2 , C2与x轴交于点B,D.若直线y=x+m与C1、C2共有3个不同的交点,则m的取值范围是()A . ﹣2<m<B . ﹣3<m<﹣C . ﹣3<m<﹣2D . ﹣3<m<﹣5. (2分) (2017·岱岳模拟) 如图是二次函数y=ax2+bx+c(a≠0)图象的一部分,x=﹣1是对称轴,下列结论:① <0;②a﹣b+c=﹣9a;③若(﹣3,y1),(,y2)是抛物线上两点,则y1>y2;④将抛物线沿x轴向右平移一个单位后得到的新抛物线的表达式为y=a(x2﹣9).其中正确的是()A . ①②③B . ①③④C . ①②④D . ①②③④6. (2分) (2019九上·渠县月考) 宾馆有50间房供游客居住,当毎间房每天定价为180元时,宾馆会住满;当毎间房每天的定价每增加10元时,就会空闲一间房.如果有游客居住,宾馆需对居住的毎间房每天支出20元的费用.当房价定为多少元时,宾馆当天的利润为10890元?设房价定为x元.则有()A . (180+x﹣20)(50﹣)=10890B . (x﹣20)(50﹣)=10890C . x(50﹣)﹣50×20=10890D . (x+180)(50﹣)﹣50×20=108二、填空题(每小题3分,共24分) (共8题;共24分)7. (3分) (2018九上·阜宁期末) 若关于x的方程x2+2x+k=0有两个不相等的实数根,则k的取值范围是________.8. (3分) (2017九上·南涧期中) 已知二次函数的图象开口向下,且顶点坐标(0,-3).请写出一个符合条件的二次函数的解析式________.9. (3分) (2017九上·巫溪期末) 三角形两边的长分别是8和6,第3边的长是一元二次方程x2﹣16x+60=0的一个实数根,则该三角形的面积是________.10. (3分)(2018·东宝模拟) 已知关于x的方程x2+2kx+k2+k+3=0的两根分别是x1、x2 ,则(x1﹣1)2+(x2﹣1)2的最小值是________11. (3分) (2019九上·天台月考) 已知二次函数,当b取不同的值时,其图象构成一个“抛物线系”,如图中的实线型抛物线分别是b取三个不同的值时二次函数的图象,它们的顶点在一条抛物线上(图中虚线型抛物线),则这条虚线型抛物线的解析式是________ .12. (3分)用铝合金型材做一个形状如图(1)所示的矩形窗框,设窗框的一边为xm ,窗户的透光面积为ym2 ,y与x的函数图象如图(2)所示.观察图象,当x=________时,窗户透光面积最大.13. (3分) (2016九上·海南期中) 关于函数y=x2+2x,下列说法正确的是________①图形是轴对称图形②图形经过点(﹣1,1)③图形有一个最低点④当x>1时,y随x的增大而增大.14. (3分) (2019九上·江山期中) 如图,已知抛物线与轴交于A、C两点,与轴交于点B,在抛物线的对称轴上找一点Q,使△ABQ成为等腰三角形,则Q点的坐标是________。
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东莞市翰林实验学校九年级上学期第一次月考
数 学 试 题
一、选择题(本大题10小题,每小题3分,共30分)
1.下面的图形中,既是轴对称图形又是中心对称图形的是( )
A
. B .
C .
D .
2.关于x 的一元二次方程222310x x
a
--+=
的一个根为2,则a 的值是( )
A .1
B C .D .
3.若一元二次方程022
=++m x x 有实数根,则m 的取值范围是( )
A. 1-≤m
B. 1≤m
C. 4≤m
D.2
1≤
m 4.用配方法解关于x 的一元二次方程x 2-2x -3=0,配方后的方程可以是( )
A .(x -1)2=4
B .(x +1)2=4
C .(x -1)2=16
D .(x +1)2=16
5.如图,将△AOB 绕点O 按逆时针方向旋转45°后得到△A ′OB ′,若∠AOB=15°,∠AOB ′的度数是( ) A .25° B . 30°
C . 35°
D . 40°
6.在如图4×4的正方形网格中,△MNP 绕某点旋转一定的角度,得到△M 1N 1P 1,则其旋转中心
可能是( ) A .点A
B . 点B
C .点C
D .点D
7.把抛物线2(1)1y x =-+的图像向左移两个单位后的顶点坐标为( ) A .(1,1) B .(1,1)- C .(1,1)- D .(1,1)-- 8.抛物线265y x x =-+的对称轴为( ) A .3=x
B .3-=x
C .6=x
D . 3
1
-
=x 9.直角坐标系内,点P (-2 ,3)关于原点的对称点Q 的坐标为 ( )
5题图
6题图
A .(2,-3)
B .(2,3)
C .(3,-2)
D .(-2,-3)
10.关于抛物线322--=x x y ,下列结论中正确的是( )
A .y 有最小值3-
B .当1>x 时,y 随x 的增大而增大
C .与y 轴交于点(0,3)
D .与x 轴交于点(3,0)、(1,0)
二、填空题(每小题4分,共24分)
11.方程042
=+x x 的解为 .
12.已知:m 、n 是方程03522
=--x x 的两根,则
=+n
m 1
1 13.圣诞节时,一个小组有x 人,他们每两人之间互送贺卡一张,已知全组共送贺卡132张,则
可列方程为
14.将一个正六边形绕着其中心,至少旋转 度可以和原来的图形重合.
15.将抛物线2y x =先向右平移2个单位长度,再向下平移1个单位长度后,所得抛物线的解析
式是 .
16.右图是抛物线c bx ax y ++=2
的图象的一部分,请你根据图 象写出方程02
=++c bx ax 的两根是_ _ ____
三、解答题(每小题6分,共18分)
17.解方程:4)2)(1(=+-x x
18.已知二次函数图象的对称轴是1=x ,且函数有最大值为2,图象与x 轴的一个交点是 (-1,0),求这个二次函数的解析式.
19.如图,已知点A 、B 、C 的坐标分别为(0,0),(4,0),将△ABC 绕点A 按逆时针方向旋转
90°得到△AB′C′.
(1)画出△AB′C′; (2)求CC ′的长.
四、解答题(每小题7分,共21分)
20.已知关于x 的一元二次方程082
2
=--k x x (k 为常数). (1)求证:方程有两个不相等的实数根;
(2)设1x ,2x 为方程的两个实数根,且11221=-x x ,试求方程的两个实数根和k 的值.
21.菜农李伟种植的某蔬菜计划以5元/千克的单价对外批发销售,由于部分菜农盲目扩大种植,
造成蔬菜滞销,李伟为了加快销售,减少损失,对价格进行两次下调后,以3.2元/千克的单价对外批发销售。
(1)求平均每次下调的百分率。
(2)如果李伟按以前的调价方案再进行一次调价,蔬菜的批发价会跌破2.5元/千克吗?
22.如图,二次函数322++=bx ax y 的图象与x 轴相交于点A (-3,0)、B (1,0),交y 轴
点C , C 、D 是二次函数图象上的一对对称点,一次函数n mx y +=1的图象经过B 、D 两点. (1)求a 、b 的值及点D 的坐标;
(2)根据图象写出12y y >时,x 的取值范围.
五、解答题(每小题9分,共27分)
23.如图, 用一段长为30 m 的篱笆围出一个一边靠墙的矩形菜园,墙长为18 m. 设矩形的一边长为
x m ,面积为y m 2.
(1)求y 与x 的函数关系式,并写出自变量x 的取值范围;
(2)怎样围才能使菜园的面积最大? 最大面积是多少?
24.如图所示,在△ABC 中,∠C =90°,AC =5cm ,BC =7cm ,点P 从点A 出发沿边AC 向点C
以1cm/s 的速度移动,点Q 从C 点出发沿CB 边向点B 以2cm/s 的速度移动. (1)如果P 、Q 同时出发,几秒钟后,可使△PCQ 的面积为4cm 2?
(2)点P 、Q 在移动过程中,是否存在某一时刻,使得△PCQ 的面积等于△ABC 的面积的一
半。
若存在,求出运动的时间;若不存在,说明理由.
25.正方形ABCD 的边长为3,E 、F 分别是AB 、BC 边上的点,且∠EDF=45°。
将△DAE 绕点D
逆时针旋转90°,得到△DCM 。
(1)求证:EF=FM ;
(2)当AE=1时,求EF 的长。
Q
P
C B
x
m。