初一错题集
初一数学期中易错题集锦

初一数学期中易错题集锦1. 选择题:一个正方形的边长增加20%,那么它的面积增加了多少?A. 20%B. 44%C. 50%D. 100%2. 填空题:已知直角三角形的两条直角边分别是3和4,那么斜边的长度是______。
3. 判断题:在等差数列中,第10项的值等于第5项的值。
A. 正确B. 错误4. 解答题:求解下列方程:2x + 5 = 3x - 7。
5. 选择题:一个长方体的长是8厘米,宽是5厘米,高是3厘米,那么它的对角线长度是多少厘米?A. 17B. 10C. 13D. 126. 填空题:将下列分数转换为小数:3/4 = ______。
7. 判断题:如果一个数的平方根是整数,那么这个数一定是正数。
A. 正确B. 错误8. 解答题:计算下列代数式的值:2(x - 3) + 5。
9. 选择题:一个圆的半径增加了20%,那么它的面积增加了多少?A. 20%B. 44%C. 50%D. 100%10. 填空题:已知一个等差数列的前两项分别是3和5,那么第10项是多少?11. 判断题:在等比数列中,第10项的值等于第5项的值。
A. 正确B. 错误12. 解答题:求解下列方程组:2x + 3y = 8x - y = 113. 选择题:一个正方体的表面积是64平方厘米,那么它的边长是多少厘米?A. 4B. 8C. 12D. 1614. 填空题:将下列分数转换为小数:5/6 = ______。
15. 判断题:如果一个数的平方根是负数,那么这个数一定是负数。
A. 正确B. 错误16. 解答题:计算下列代数式的值:3(x + 2) - 7。
17. 选择题:一个圆锥的底面半径是3厘米,高是5厘米,那么它的体积是多少立方厘米?A. 314B. 157C. 254D. 46218. 填空题:已知一个等比数列的前两项分别是2和4,那么第10项是多少?19. 判断题:如果一个数的立方根是整数,那么这个数一定是正数。
初一上册数学错题集

初一上册数学错题集姓名:杭泽林 2014年11月常州外国语学校七年级周末作业一16、一收费员从水厂出发,向东走了2千米到达小聪家,继续向东走了1.5千米到达小华家,又向西走了5千米到达小文家,最后回到水厂。
1、以水厂为原点,以向东方向为正方向,用一个单位长度表示1千米,你能在数轴上表示出小聪家、小华家和小文家的位置吗?2、小聪家距小文家多远?3、收费员一共走了多少千米?常州外国语学校七年级周末作业二15、数轴上原点右边4.8厘米处的点表示的有理数是32,那么,数轴原点左边18厘米处的点表示的有理数的常州外国语学校第四单元练习1、小华在某月的日历中圈出了三个数,并算出这三个数的和是39,则小华圈出的三个数的排列形式不可能是:()A、xB、x x xC、x xD、x xX x x x2、如图是一个长方形块图,由6个大小不完全相同的正方形组成,设中间最小的一个正方形边长为1,则这个长方形的面积为3、某物流公司的甲、乙两辆货车分别从相距300千米的A、B两地同时出发相向而行,并以各自的速度匀速行驶,两车行驶1.5小时时甲车先到达配货站C地,此时两车相距30千米,甲车在C地用1小时配货,然后按原速度开往B地;乙车从B地行驶2小时时也到C地,未停留继续开往A地。
(友情提醒:画出线段图帮助分析)(1):乙车的速度是千米/小时,B、C两地的距离是千米,A、C两地的距离是千米;(2):求甲车的速度及甲车到达B地总共用的时间;(3):乙车从B地出发多长时间,两车相距150千米?常州外国语学校七年级周末作业五8、有一列数:-1/2、2/5、-3/10、4/17……,那么第n个数是常州外国语学校七年级周末作业七1、为鼓励节约用水,某地推行阶梯式水价计费制,标准如下:每月用水不超过17m3的按每立方米a元计费;超过17m3而未超过30m3 的部分按每立方米b元计费;而超过30m3的部分按每立方米c元计费。
某户居民上月用水35m3,应交水费为常州外国语学校七年级周末作业九10、若:(2x+1)=常州外国语学校七年级第十二周周末作业1、幼儿园有一批卡通书,若3个小朋友合着一本,则多2本;若2个小朋友合着看一本,则有9个小朋友没有书看,共有多少个小朋友?1如图,已知矩形ABCD中,AB=3cm , BC=5cm,点P从点A出发,沿着矩形的边逆时针运动,速度为1cm/s;同时点Q从点C出发,也沿着矩形的边逆时针运动,速度为1,8cm/s。
初一英语上册错题集及分析

1.错误题1:---What’s this in English? -----_______an orange orange.A. This isB.This’sC. ItD. It’s错误原因分析:错误率高,有this引导的问句中,为了避免重复,往往用it来代替它。
答语中只有表语,缺乏主语和系动词,故选D.2. 错误题2:His a boy.错误原因分析: 学生不了解主格代词与物主代词的差别,仅依据汉字信息“他”使用英语词汇。
改正: He’s a boy.3. 错误题3:Look at, this is my room..错误原因分析:look 与look at混淆, 不了解at 何时使用.改正:Look! This is my room.4.错误题4:The baseball on the dresser.错误原因分析:这类错误尤其多见于含介词短语的英语句子,主要原因是学生受汉语表达影响,如“棒球在梳妆台上”,忽略了英语句子中的谓语动词。
改正:The baseball is on the dressser.5.错误题5:His books are in backpack.错误原因分析:学生习惯于汉语思维,即使使用冠词也拘泥于翻译“一(个...)”或“这(些)、那(些)”,没有使用冠词的意识。
改正:His books are in the backpack.6.错误题.6:The desks is new. The chairs is green.错误原因分析:汉语中主谓没有数的变化,初学英语的学生往往忽视英语中主谓在人称和数量上的一致性。
改正: The desks are new. The chairs are green.7.错误题7:I found this a set of keys in the found and lost case.错误原因分析:指示代词和不定冠词混淆,对词组的熟悉程度不够,this和 a 放在一起,缺乏语言习惯。
初一错题集1

初一错题集 Unit1-41.They have some rulers in their bags.(同义句)2.Are you ?Yes, we are brothers.(twin)3.You (not be) friendly to your classmates.4.What does your father often to you? He often tells me not to inclass.A.s ay talkB.talk sayC.say sayD.talk talk5.My father with me (fly) a kite every Saturday.6.It takes about ten minutes to walk to the museum.(对划线部分提问)to walk to the museum.7.Our school is near the zoo.(同义句)Our school is the room.8.Please take your books after school.A.t o homeB.your homeC.homeD.at home9.Lily’s watches sports news at night.A.twins brother;much tooB.twin brothers;too muchC.twin brother;too muchD.twins brothers;too many10.I usually sit the classroom,so that I can hear the teacher who likes to standthe class clearly.A.i n front of;in the front ofB.in the front of;in front ofC.in front of;in front ofD.in the front of;in the front of10.I hope you and your family .A.w ellB.are well lC.fineD.are good11.Yao Ming, (like)his parents, (like)playing basketball very much.12.The supermarket (close)at 9p.m..It is (open)between 9a.m.and 9p.m..So it is (close)from 9p.m. to 9a.m..13.(read) English every day. (read)can help you improve( 提高)yourEnglish.(read)14.Would you (go) to the zoo tomorrow.15.Do you often do your homework after (have)dinner.16.My favourite fruit (be)apples.17.There are different kinds of kites (fly)in the sky.18.If a girl doesn’t know wear,she can ask her best friend for help.A.what toB.how toC.what canD.how can19.What’s your family like? .A.They are kind.B.It’s a happy one.C.They are tall.D.They like sports.20.He is never late for school? ,he is always the first to get to s chool.A.Yes,he does.B.No,he isn’t.C.Yes,he is.D.No,he doesn’t.21.The books are one of my (hero).Jerry Lin Shuhao is one of jimmy’s(hero).He plays basketball well.22.Look!Each girl in our class (have)a new shirt now.23.(chat)with each other online is fun.24.He is one of the (good)students in our class.25.She does (well)in swimming of us three.26.does Andy’s father look? He looks strong and tall.A.HowB.WhenC.WhereD.What27.Mary;s daughter looks good the dress.A.w ithB.inC.onD.at28.I go to school on weekdays.(同义句)29.What do you get (介词)your birthday?30.Good morning (介词)you.31.What about (wake) (he)up?He has much homework(do).32.We have fun (chat)with each other at lunch.33.Would you please (not shout)in the library, it’s not polite.34.Look,the window is (open)now,please close it.37.Mum (get)ready for supper,while I (write)my home.38.I hope you our home one day,Daniel.A.to visitB.visitC.will visitD.are visiting39.41.Here for you.A.are some good newsB.is some good newsC.are some piece of good newsD.is some pieces of good news.42.There are many flowers on sides of the street.A.eachB.everyC.bothD.all43.Let’s(be) at home together this afternoon.44.There are some pictures the wall and some windows the wall,too.A.on onB.on inC.in onD.in in45.Jill, (not be)late for the meeting.46.Is the girl a dress your classmate?A.toB.onC.inD.with47.48.are good friends.A.I you and DickB.Dick you and IC.You I and DickD.You Dick and I49.Look at today’s newspaper.Some news really interesting.A.doesB.isC.areD.do50.We should “thank you” when someone lends something to us.A.tellB.speakC.sayD.talk51.She has a sister,and he has ,too.A.the oneB.onesC.oneD.her52.One of the students often her with her English in the class.A.helpB.to helpC.helpingD.helps53.I that I can send my best to Kitty on New Year`s Day.Wonderful! I believe your dream on that day .A.hope, wish, comes trueB. hope, wishes, comes trueC. wish , wishes, comes trueD. wish, hopes , come true.54.Excuse me , could you English in class?Yes, of course. I am very good at English stories.A.Say, talkingB. tell, sayingC. Speak, tellingD. Tell, speaking55.Who sports in your family? My brother and I .A.Likes, isB.like, amC. Like, areD. Likes, do56.I live far away from the school and I often a bus to school. What about you?I go to school , it takes me about ten minutes.A.by, on bikeB. take, by bikeC. by, ride a bikeD. take, ride a bike.57.We have a (parent) meeting once a month.58.Today is Teacher`s Day, best to you ,Miss Wang.59.The students go out for a trip twice a week. (对划线部分提问)do the students go out for a trip?lie does after-school activities in the afternoon. (否定句)Millie61.I can`t hear you after-school activities in the afternoon.(good) on the phone.62.Where your family (have) breakfast on Sundays.63.I have daughter.A.A eight-year-oldB. eight years oldC. An eight-year-oldD. Eight-years-old64.They come from . They are (英国)65.He with his family in Nanjing now. (live)66.He often others, and he is (help)67.How many are there in your school? (年级)68.Look, the window is (open) now, please close it.69.There is no salt in the kitchen. Would you like t o get ?A.itB. oneC. someD. any70.Don`t make Kitty that. She is tired. (do)71.72.She every day.A.Walk homeB. Walk to homeC. Walks homeD. Walks to home73.What (其他的) do you want to drink?74.One of the boys (play) football now.75.the girls like badminton? (like)76.American people usually rice.(eat)77.78.It is fun (read) an (interest) book.79.We have fun (travel) all over the world.80.The parents` meeting begins two o`clock the afternoon November 15th.A.at , in , ofB. At, on , on ,C. At, on , ofD. In , in , on。
初一数学错题集

初一数学(上)错题集1、已知一个角的两边分别平行于另一个角的两边,结合下列图形,探究这两个角之间的关系。
(4)若一个角的两边分别平行于另一个角的两边,且一个角比另一角的2倍少30°,则这两个角分别是多少度?2、如图,将面积为a2的小正方形与面积为b2 的大正方形放在一起,(b﹥a﹥0)(1)a、b表示三角形ABC的面积;(2)计算当a=2,b=5时,三角形ABC的面积。
3、某服装厂计划一周生产2100套服装,平均每天生产300套,由于各种原因实际每天生产量与计划相比有出入,下表是某周的生产情况,以300为基准(超过少生产一套扣8元,那么该厂工人这一周的工资总额是多少?4、让我们轻松一下,做一个数字游戏:第一步:取一个自然数n1=4,计算n12+1得a1;第二步;算出a1的各位数字之和得n2,计算n22+1得a2;第三步:算出a2的各位数字之和得n3,计算n32+1得a3;……以此类推则a2014=5、如图,两条平行直线a,b上分别有点A1,A2,A3,A4,B1,B2,B3,则过这7点中的任何2点画直线,不同的直线共有()条。
A1, A2, A3, A4B1, B2, B36、把50个同样大小的立方体木块堆砌成如图所示的形状,现从前、后、左、右和上面五个方向朝这堆木块喷漆,则有()块木块完全喷不到漆。
7、已知当x=1时,3ax3+bx2-2cx+4=8,并且ax3+2bx2-cx-15=-14,那当x=-1时,5ax3-5bx2-4cx+2015的值是()。
8、观察下面一列数:-1,2,-3,4,-5,6,-7……,将这列数排成如-12 -3 4-5 6 -7 8 -99、如图,四边形ABCD 的对角线AC ,BD 交于点O ,如果我们把恰有1条边相同的2个三角形称为1对“共边三角形”,,那么图中共有 ( )对“共边三角形”。
10,以[x]表示不超过x 的最大整数(例如:[π]=3,[-27]=-4),记A=[x ]+[2x ]+[3x ]+[4x ],在所有的正整数中,有些数是A 取不到的,把所有A 取不到的正整数从小到大排起来,第10个数是( )。
初一数学易错题集成

正解:都不正确.(1)缺少原点;(2)单位长度不一致;(3)有两处
错误.①缺少正方向;②负数的排序错误,从原点向左依次就是-1,-2,
….
10.下列语句:①所有整数都是正数;②所有正数都是整数;③小学学
过的数都是正数;④分数是有理数;⑤在有理数中除了负数就是正数.
其中正确的语句个数有( )
A.1
B.2
初一数学易错题集成
1.“带负号的数都是负数”,这种说法正确吗?
错解:正确.
错因分析:错解的原因是误认为带负号的数一定是负数.事实上,只从
带“+”或“-”来判断是正数还是负数是不准确的,如:-a不一定表示负
数.a=-1时,-a恰好是正数.
正解:错误.
2.如果水位上升4米记作+4米,那么-2米表示的意义是什么?
A.1个
B.2个
C.3个
D.4个
错解:C
错因分析:正整数、0、负整数统称整数,故①正确.0既不是正数,也
不是负数,②也正确.数的范围扩大到有理数后,奇数、偶数的外延也
由自然数扩大为整数,能被2整数的整数是偶数,不能被2整除的整数是
奇数,③正确.我们把正整数和0统称为非负整数,也叫自然数,0是最
小的自然数,所以④是错误的.0不一定表示没有,它是正数和负数的分
乘,再把所得的积相加,但错解却漏乘了-1;二是忽视了括号内各数的
符号,-12×=12×,而不是-12×.
正解:原式=-12×+12×-12×-12=-7-10-3+12=12.
22.计算:24÷.
错解:原式=24÷-24÷-24÷=-264.
错因分析:有理数的乘法分配律:a(b+c)=ab+ac,但除法却没有相应的
初中语文七年级错题集

目录初一语文初一语文秋季学习规划月份知识框架9月记叙文阅读指导A、作文人物描写A、语基之仿句10月记叙文阅读指导B、说明文阅读指导11月记叙文阅读指导C、作文人物描写B、语基之病句12月作文技巧训练、寓言童话赏析1月小小说阅读、名著重难点:1、记叙文阅读技巧2、说明文阅读技巧3、小说阅读技巧4、名著知识【记叙文阅读之字词分析】1、例题(2011·黑龙江牡丹江市)《父亲那只寂寞的手》(1)联系上下文,说说第⑥段中加点词语的作用。
(2分)而那个年轻人,也不再看妻子,他微微闭上眼睛,短短的睫毛颤巍巍地在灯光下着。
抖动..【错解】:说明这个年轻人很激动。
【错解原因分析】:词句效果题,要注意,首先联系上下文,其次再对词语的分析,分为手法和表现力,最后对本句甚至对人物对全文的情感作用。
【正解】:运用了动作(细节)描写,生动地表现了儿子感受到父爱时内心的激动。
评分标准:(2分)描写方法1分,人物心理1分。
【变式训练】1、(2009福州中考)《一双脚上的修养》①市图书馆离我家很近,每逢双休日,我都会到图书馆的阅览室去翻阅一些报纸和杂志。
每次来这里,总看到座无虚席的场面,有时,大家还会围绕一些文学现象进行一些交流。
在这紧张而喧嚣的都市里,能保持一份阅读的闲情,是难能可贵的。
所以,在我看来,这里的每一个人,都有着一定的层次和修养。
②北方冬天的雪大,雪一下,许多麻烦就随之而来了。
走在街上,鞋上会粘满脏雪,从天寒地冻的室外进入室内。
脏雪马上就会化作污水。
所以人走过的地方,往往会留下两行黑乎乎的脚印。
正是在一个雪天,我走进阅览室时发现了异样。
屋子里多了一个擦地的女工,她看我进来,竟紧张地盯着我,手操托布,如临大敌。
我故作视而不见,可感觉告诉我,她正跟在我的身后,猛回头,把她吓了一跳,自己也吓了一跳。
吃惊于自己留下的那行脚印。
在淡黄的地板上,显得如此扎眼。
而那个擦地女工,正在奋力擦抹。
③坐到座位上,想着刚才的脚印,愧怍油然而生,再也无心看书了。
初一英语错题集

初一英语错题集错题集〔一〕 22/12/20221. The final test is difficult . Only few students have passed the exam, they?A. haven’tB.haveC.didn ’t2.Take it easy. The police here. Everyone OK.A.is ing, will beB.are ing, will beC.es. is3. —I felt really sorry for Liu Xiang when I watched him down in the match. -- A.falling, So I didB.fall, So did IC.falling, So did I4.My mother dressed us the same cloyhes.A.inB.onC.with5.Now I am growing old and I feel very different my twin pother.A. inB.fromC.with6.Several years and David became a strong young man.A.passedB.pastC.goes by7.Suddently he was awakened and heard his uncle to his outside.A.shoutB.shoutingC.shouted8.Mr.Shut became angry and shouted , ‘Why you e out yet?’A.don ’tB.didn ’tC.haven ’t9.Don ’t you think we really need a dictionary ?A.to look the word upB.to look the word up inC.to look the word up with10.If you want to study English well,please every morning.It helps .A.read aloud, a lot ofB.read loudly, a lotC.read aloud, a lot11.My mom never give me pocket money , so I have to make money some other ways.A.inB.withC.by12.On holidays,give your customers coupons(优惠券) they will keep ing back to you for your service or products.A.as soon asB.so thatC.now that13.Premier Zhou for many years,but he still lives in the hearts of Chinese people.A.has diedB.has been diedC.has been deadA.Either,usingB.Neither, to useC.Both,use15.Children and adults always don’t know how to deal with or treat someone a disability.A.inB.forC.with16.I was that I would be late for school.A.afraidB.sureC.sorry17.Teenagers can’t drive on busy streets .A.without being allowedB.without permitC.without being allowed to18.You must tell your daughter it is in this mysterious place you met your husband.A.that, whereB.that,thatC./, where19.He told me he fished for a living to his daughter.catedB.supportC.offer20.What a mess! Your table different things. Why not clean your table?A .cover with B.is covered with C.is covered21.In America,teenagers can’t beer by law.A .offer to B.be offered C.be offered to22.I never saw her angry ,never saw her .A .cry B.smiling C.crying23.I cleaned the desk carefully and found some papers -- a photo of my father and a one-page letter.A .inside B.indoors C.outside24.Something . The house is filled with strangeA .smells badly,smell B.is smelt badly,smellsC.smells bad,smells25.It ’s to get a C than to fail in the exam. So take it easy. Try harder next time.A .a less problem B.less a problem C.less of a problem26.People read the result of the medical research by Dr. Smith and learned a lot from it.A.to doB.doingC.done27.Audi as a car pany is very famous in the world. It is famous its popular cars and special designs.A .as B.for C.with28.Now it that a two-wheel bike of 2022 will einto our life.A .is said B.was said C.says29.The e-bike doesn’t use any stratighly.A .electric B.electrical C.electricityA.evenB.althoughC.even though31.Dolphins use different sounds to information with each other.A.exchangeB.changeC.discuss32.The groups really cool clothes. But that’s not really important me.A.put on,toB.wear, forC.are wearing, to33.I listen a CD Heart Stering.A.of, calledB.to,with the name ofC.to, calling34.--Must I finish the wor k before five O’clock.--No. You finish it eight.A.musn ’t, atB.needn ’tC.can,by35.I repeat the story by teacher just now.A.was letB.is letC.was let to36.Thanks to the project and the kindness of his family and neighbours, he was able to recive anoperation just to prevent the illness from getting worse.A. in timeB.on timeC.at the same time37.--It ’s kind you to e to see me.--It ’s my pleasure. You were so kind me.A.of, withB.for, withC.of, to C.for,to38.You may go fishing if you work A.is done B.will be done C.has done39.He still remembers the days he spent with your family.A.whenB.whereC.thatD.on which40.Mr. White car had been stolen, came to the policeman.A.whoB.thatC.whoseD.which41. you didn’t get good grades, you’d better study harder.A.Now thatB.WhenC.Although42.There used to an old temple in this village, there?A.have, didn’tB.be, usedn’tC.be,did43.Only the help of the teachers and parents deal with problems easily.A.with, we canB.for,can weC.with,can weof them has a chance to another town.A.Both, to moveB.Everyone, to moveC.Every one,of moving错题集〔一〕 2022年12月22日 1.2. 3.4. B B B watch sb do sth表示看见某人做某事,也指看某人某物的总过程;而doing 表示看见正在做A 首先,dress 是及物动词,意为“为... 穿衣”,用法是dress sb,如:The babysitter dresses the baby everyday.保姆每天都要给宝宝穿衣。
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1.一个三项式与一个二项式相乘,在合并同类项之前,积的项数是( ). A .三项 B .四项 C .五项 D .六项 2.(
)()
2
3
342a b
ab -÷= .
()()()24212121+++的结果为 .
3.下列各式的计算是否正确,将错的改正过来
()011101010-÷=; ()()
4210271000-⋅⨯=;
()()3
130182-⋅⎛⎫-÷-= ⎪⎝⎭; ()()4
41410110--⎛⎫
-÷-=- ⎪⎝⎭
4.当3x =-时代数式5
3
8ax bx cx ++-的值为6试求当3x =时,5
3
8ax bx cx ++-的值.
5.已知∠α=72°36′,则∠α的余角是________. 6.请先观察下列算式,再填空:
181322⨯=-, 283522⨯=-.
①=-22578× ; ②29-( )2
=8×4; ③( )2
-92
=8×5; ④213-( )2
=8× ; ⑴通过观察归纳,你知道上述规律的一般形式吗?请把你的猜想写出来.
⑵你能运用本章所学的平方差公式来说明你的猜想的正确性吗?
7.方程2m+x=1和3x-1=2x+1有相同的解,则m 的值为( )
8.求方程│3x│=18的解
9.若方程2ax-3=5x+b 无解,则a ,b 应满足
10.在800米跑道上有两人练中长跑,甲每分钟跑300米,乙每分钟跑260米,•两人同地、同时、同向起跑,t 分钟后第一次相遇,t 等于( ).
11.若a2+b2+4a-6b+13=0,试求a b的值.
12.某商品的利润是20%,如果进货价降低20%,出售价保持不变,那么利润率将是多少?
13.某人买了200元的西红柿,如果以每千克2.8元卖出,可赚四成,由于气候因素,除了一部分质量好的以2.8元卖出外,其余的按每千克2元卖出,所以实际上只赚了一成,问其中有多少千克的西红柿买了2.8元?
14.一杯牛奶,喝去20%加满水搅匀,再喝去50%后,杯中的纯牛奶占杯子容积的()%。
15.一项工程,甲2/3小时完成,乙0.5小时完成,二人合作多少小时完成?
16.水结成冰,体积增大3/22,冰化成水体积减少多少?
17.2(3+1)(32+1)(34+1)(38+1)(316+1)(332+1)+1
18 . (2a-b)2(4a2+b2)2(2a+b)219. (2a+b-3c)(2a-b-3c) 20. 210+(-2)10 21.若9m+3×27m+1=81,m=( )
22.若3x=12,3y=4,则27x-y+1=( )
23.已知2x+5y=3,求4x×32y的值。
24.已知22x+1+4x=48.求x的值。
25、如图5,小明从A 处出发沿北偏东60°方向行走至B 处,又沿北偏西20
方向行走至C 处,此时需把方向调整到与出发时一致,则方向的调整应是( )
A .右转80°
B .左转80°
C .右转100°
D .左转100°
26.如果两个角的两边分别平行,而其中一个角比另一个角的4倍少30
,那么这两个角是( )
A . 42138 、;
B . 都是10
;C . 42138 、或4210 、;D . 以上都不对 27.、下列语句错误的是( )
A .连接两点的线段的长度叫做两点间的距离;
B .两条直线平行,同旁内角互补
C .若两个角有公共顶点且有一条公共边,和等于平角,则这两个角为邻补角
D .平移变换中,各组对应点连成两线段平行且相等
28.已知,如图,CD ⊥AB ,GF ⊥AB ,∠B =∠ADE ,试说明∠1=∠2.
8、某种商品价格a 元,请解释
3
1
a 元的含义。
11、下列各式符合代数式书写规范的是( )
A 、
a b
B 、a ×3
C 、3x -1个
D 、22
1n 23、求图1中阴影部分面积的代数式,并求出当x=3时阴影部分面积(π取3.14)
24、某商店有两个进价不同的计算器都卖了80元,其中一个赢利60%,另一个亏本20%,在这次买卖中,这家商店( )
A 、不赔不赚
B 、赚了10元
C 、赔了10元
D 赚了50元
F 2
1
G
E D
C
B A
25、当a<0时,化简
a
a
a ||,得( ) A 、-2 B 、0 C 、1 D 、2
26、小宇同学在一次手工制作活动中,先把一张矩形纸片按图1的方式进行折叠,使折痕的左侧部分比右侧部分短1cm ,展开后按图2的方式再折叠一次,使第二次折痕的左侧部分比右侧部分长1cm ,,再展开后,在纸上形成的两条折痕之间的距离是( )
A 、0.5cm
B 、1cm
C 、1.5cm
D 、2cm
27.用四四舍五入法对30435(保留3个有效数字)取近似数为________.
28.已知点B 在线段AC 上,AB=8cm,AC=18cm,P 、Q 分别是AB 、AC 的中点,则
PQ=________.
第一次折叠 第一次折叠 图 1 图 2 ( 第 10 题图 )。