广东省深圳市宝安区 新安中学(集团)外国语学校2019-2020学年七年级下册第一次联考测试数学试卷
2020-2021深圳市新安中学七年级数学下期末第一次模拟试卷(含答案)
解：A、1600名学生的体重是总体，故A正确；
B、1600名学生的体重是总体，故B错误；
C、每个学生的体重是个体，故C错误；
D、从中抽取了100名学生的体重是一个样本，故D错误；
故选：A．
【点睛】
本题考查了总体、个体、样本、样本容量，解题要分清具体问题中的总体、个体与样本，关键是明确考查的对象．总体、个体与样本的考查对象是相同的，所不同的是范围的大小．样本容量是样本中包含的个体的数目，不能带单位．
A．（2，﹣1）B．（4，﹣2）C．（4，2）D．（2，0）
12．某中学计划租用若干辆汽车运送七年级学生外出进行社会实践活动，如果一辆车乘坐45人，那么有35名学生没有车坐；如果一辆车乘坐60人，那么有一辆车只坐了35人，并且还空出一辆车．设计划租用x辆车，共有y名学生．则根据题意列方程组为（ ）
A． B．
B、∠A＝∠EBD不能判断出EB∥AC，故B选项不符合题意；
C、∠C＝∠ABC只能判断出AB＝AC，不能判断出EB∥AC，故C选项不符合题意；
D、∠A＝∠ABE，根据内错角相等，两直线平行，可以得出EB∥AC，故D选项符合题意．
故选：D．
【点睛】
此题考查平行线的性质，正确识别“三线八角”中的同位角、内错角、同旁内角是解题的关键，只有同位角相等、内错角相等、同旁内角互补，才能推出两被截直线平行．
A． B． C． D．
7．如图，把一个直角三角尺的直角顶点放在直尺的一边上，若∠1＝50°，则∠2＝（ ）
A．20°B．30°C．40°D．50°
8．如图，已知∠1+∠2＝180°，∠3＝55°，那么∠4的度数是（ ）
A．35°B．45°C．55°D．125°
9．下列图中∠1和∠2是同位角的是( )
2019-2020学年深圳市宝安区第一学期七年级答案V4.0 20191030(1)
2019-2020学年第一学期宝安区期末调研测试卷七年级语文答案一、单项技能考查（每题2分，共10分）1. C（A 贮 zhù澄chéng B庇bì咄duō D琢zhuó匐 fú）2.A（B云霄 C菜畦 D狭隘）3.B（喜出望外：遇到出乎意料的喜事而特别高兴。
平时学习刻苦认真，取得好成绩在意料之中，用“喜出望外”不妥。
）4.D （③句引出下文，写在胡杨林看到的景物；⑥句中的薄雾跟⑤句中的雾气有明显的关联，—个而字，可以看出⑤是承接⑥的转折句。
①④②句是写骑着白马的骑手，②句的“他”承接④句的骑手。
故答案为D．③⑥⑤①④②。
）5.C（刘义庆是南朝宋文学家，宋是中国南北朝时代南朝的第一个朝代）二、诗文能力考查（24分）（一）课内外文言文阅读考查（12分）6. ⑴淫慢则不能励．精。
（振奋）⑵年与时驰．，意与日去。
（疾行，指迅速逝去）⑶遂．不能有所成。
（于是，就）⑷故．特作书戒之。
（所以，因此）7（1）不能淡泊自守就无法明确志向，不能宁静专一就无法达到远大目标。
（2）希望你们一定要仔细思考我说的话并深刻反省自己呀！8．甲文告诫自己的孩子（1分）要静心学习、俭朴养德（1分）。
乙文希望诸弟（1分）戒除傲气自满之气（1分）。
【文段二译文】三房十四叔不是不勤读，只因傲气太盛，自满自足，便不能有所成就。
京城之中，也有不少自满的人，有见识的人看见他们，不过冷笑一声罢了。
又有当名士的，把科名看得和粪土一样，或者喜欢作点古诗，或者搞点考据，或者好讲理学，沸沸扬扬自以为压倒一切。
有学识的人见了，认为他们的成就也没有多少，也只好冷笑一声罢了。
所以我们用功，去掉傲气，力戒自满，不为别人所冷笑，才有进步。
弟弟们平时都谨慎退让，但多年小考没有中，恐怕是因为愤激已久，以致产生骄惰的习气，所以特别写信告诫。
务必要仔细想一想我说的话深切地省察！幸甚幸甚！1。
2019年深圳市深圳外国语学校七下期中考试
深圳外国语学校2019-2020学年第二学期七年级期中测试数学试卷一、选择题1.下列各题的计算中，正确的是A.()532a a =B.()63293a a -=- C.()()76a a a -=-⋅- D.6332a a a =+ 2.已知，1=+b a 则b b a 222+-的值为 A.1 B.3 C.4 D.03.若()()，223y x xy =-⨯则括号里应填的单项式是 A.y 3- B.xy 3 C.xy 3- D.y x 234.若()()()，nx x x x -=++-164222则n 的值等于 A.6 B.4 C.3 D.25.下列多项式,为完全平方式的是A.241a +B.1442-+b bC.442+-a aD.22b ab a ++6.已知()613--+x a x 能被2-x 整除,则a 的值为 A.1 B.-1 C.0 D.27.已知直线，∥21l l 一块含30°角的直角三角板如图所示放置，∠1=35°，则∠2等于A.25°B.35°C.40°D.45°8.如图，三角形纸片ABC 中，∠A=65°，∠B=75°，将∠C 沿DE 对折，使点C 落在△ABC 外的点'C 处，若∠1=20°，则∠2的度数为A.80°B.90°C.100°D.110°9.下列尺规作图，能判断AD 是△ABC 边上的高是10.一定能确定△ABC ≌△DEF 的条件是A.AB=DE,BC=EF,∠A=∠DB.∠A=∠E,AB=EF,∠B=∠DC.∠A=∠D,AB=DE,∠B=∠ED.∠A=∠D,∠B=∠E,∠C=∠F11.在如图的方格纸中，每个小方格都是边长为1的止方形，点A 、B 是方格纸中的两个格点(即正方形的顶点)，在这个5×5的方格纸中，找出格点C 使△ABC 的面积为2个平方单位，则满足条件的格点C 的个数是A.5B.4C.3D.212.如图，在△ABC 中，∠BAC=90°，AD 是高，BE 是中线，CF 是角平分线，CF 交AD 于点G ，交BE 于点H ，下面说法不正确的是A.△ABE 的面积=△BCE 的面积B.∠AFG=∠AGFC.BH=CHD.∠MAG=2∠ACF二、填空题13.计算:=⎪⎭⎫ ⎝⎛÷-23212x x ________. 14.若()，1512=--x 则x 的值是________. 15.如图，直线，∥n m 以直线m 上的点A 为圆心，适当长为半径画弧，分别交直线n m 、于点B 、C ，连接AC 、BC ，若∠1=30°，则∠2=______°.16.已知:如图，BD 为△ABC 的角平分线，且BD=BC ，E 为BD 延长线上的一点，BE=BA ，过E 作EF ⊥AB ，F 为垂足，下列结论:①△ABD ≌△EBC ；②∠BCE+∠BCD=180°；③AD=EF=EC ；④AE=EC ，其中正确的是________(填序号)三、解答题17.化简:(1)()324232b a b a ÷- (2)()()()23125--+-x x x18.已知，，3223==m m y x 求()()()m m m m y y x y x ⋅-+32632的值。
2019-2020学年广东省深圳市宝安区七年级(下)期末英语试卷(附答案详解)
2019-2020学年广东省深圳市宝安区七年级（下）期末英语试卷一、单选题（本大题共15小题，共15.0分）1.--The doctor told me to give up eating junk food.--He's right.Junk food is bad for our health.（）A. enjoyB. keepC. stop2.These two dresses are both nice, but I prefer the purple one.（）A. want…bestB. like…betterC. enjoy…less3.-This summer holiday,I will go sightseeing in Shanghai.-Wish you a good trip！（）A. enjoy myselfB. buy beautiful thingsC. visit interesting places4.-The boy is known as"the hero of the village".-Yes,because he rescued a little girl from the river.（）A. returnedB. savedC. gave5.-After looking for a job for months,he found one finally.-Really？What does he do now？（）A. in a wayB. at lastC. at first6.-Yesterday was your birthday.What did you do？-Well,nothing special.It was just an ordinary day for me.（）A. usual dayB. an unusual dayC. a different day7.-The information is valuable.Thank you.-That's all right.I'm glad that I can help.（）A. quite newB. very carefulC. very useful8.-Can we go now？-Sorry,please wait a moment.I have something to deal with.（）A. a second timeB. a long timeC. a short time9.-In many buildings,hot water runs _________pipes to keep rooms warm.-Yes,it's very common（常见的）in the north.（）A. besideB. acrossC. through10.-Here is the menu.Please______ the dish you like with the pencil.-Well,thanks.Would you please get me a glass of water first？（）A. giveB. pickC. miss11.-Where should I put my coat？-_________you like.Just make yourself feel at home.（）A. ElsewhereB. NowhereC. Anywhere12.-Did the famous star_______ in the concert？-No.It's said he didn't come to our city at all.（）A. appearB. launchC. interview13.-How is your stage play（舞台剧）going？-Not good.No one would like to _______the bad man in it.（）A. actB. pushC. laugh14.Over the past 10 years,he has _______more than 100，000 photos of trains in nearly 30countries and regions（地区）.（）A. boughtB. takenC. drawn15.-_______water refers to water that is not salty.-Yes.It's important in our daily life.（）A. FreshB. CleanC. Safe二、完形填空（本大题共10小题，共10.0分）John is a policeman.He helps to(16)us and our things safe.He is busy with his work.He lives with his parents.But it's(17) his work,and it (18) him one and a half hours on the bus every day,so he leaves his parents' home and finds a new house near the place he works.It is Mother's Day today.He doesn't have time(19)home.He buys some roses at a flower shop.And he asks the shop assistant to send them to his(20)for him.At this time,a little boy comes in.He wears a（n）(21) T-shirt."How many roses can I get for only five dollars？"The little boy asks.The shop assistant tells him the roses are expensive,and he can buy some carnations（康乃馨）."No,my mum is ill,but I don't have time to be with her,so I want to get the best thing for my mum.Roses are her favourite."After hearing this,John knows(22)the boy feels.It is not easy for the boy to buy them,(23) John buys the boy the roses.The boy is so happy and runs out.John(24)the boy to go out.He finds that the boy walks into a cemetery（公墓）.He cries and says,"God,please help me (25)my mum and tells her how much I love her."After seeing this,John comes back to the shop.He wants to take the flowers home himself.16. A. let B. keep C. bring17. A. near B. close to C. far from18. A. makes B. needs C. takes19. A. to go B. to get to C. to arrive at20. A. father B. Mother C. grandma21. A. old B. new C. big22. A. why B. what C. because23. A. but B. so C. because24. A. follows B. sends C. waits25. A. bring B. find C. take三、阅读理解（本大题共20小题，共30.0分）AShopping online is one of the most important part of life now.Taobao is China's largest online shopping website.People spend lots of money on Taobao every year.Now more and more Internet users enjoy online shopping.More online shoppers are students or young workers.More women shop online than men.Clothing and home-use products are the most popular online.It's said that people spent more than 250 billion yuan on online shopping last year,80% through Taobao.People can find almost everything they need on Taobao,from clothes to books,DVD players and so on.Shopping on it is very safe and convenient.too.You can finish it without leaving home.If you receive the products from the sellers,but you aren't happy with them,the shop keeper will not get the money.You can also get your money back if you want to return the products.26.According to the article,we know Taobao is ______ .A. a shopping mallB. an online shopperC. an online shopping siteD. a supermarket27.Most online shoppers are ______ .A. youngB. oldC. babiesD. mothers28.What are the most popular products on Taobao？______A. Clothes and DVD players.B. Clothes and books.C. Food and clothing.D. Clothing and home-use products.29.What does the underlined word "convenient" mean in Chinese？______A. 有竞争的.B. 方便的.C. 附近的.D. 适合的.30.What is the passage about？______A. Our romantic life.B. Our convenient life.C. Safe shopping online.D. Shopping on Taobao.BDo you know Singapore？Yeah．It's a beautiful and clean country and it's in Southeast Asia．The weather there is warm all year round．There are lots of trees，flowers and rivers in the country．So it is good and fun for people to have a vacation in Singapore．There are also many Chinese people in Singapore．So you can eat different kinds of Chinese food，such as dumplings，rice and noodles．They are all delicious!If you go to Singapore one day，you must go to visit Sentosa．Sentosa means"peace and quiet"in Malay．It is very popular with people from all over the world．There are some peaceful butterflies，pink dolphins and elephants there．If you go to Singapore，you'll have a good time．31.Singapore is a（n）______ ．A. cityB. countryC. islandD. river32.Which of the following is TRUE？______A. There are few flowers and trees in Singapore．B. It's warm all year round in Singapore．C. You can't swim all year round in SingaporeD. You can't eat dumplings in Singapore．33.Which Chinese food can you find in Singapore？______A. Dumplings．B. Rice．C. Noodles．D. All of the above．34.What does Sentosa mean in Malay？______A. Happiness and peace．B. Peace and warm．C. Happiness and quiet．D. Peace and quiet．35.Which animals aren't there in Sentosa？______A. Butterflies．B. Pink dolphins．C. Pandas．D. Elephants．CIn the US，people prefer waiting for a table to sitting with people they don't know.This means a hostess may not seat a small group until a small table is available（有空的），even if a large one is.If you are sitting at a table with people you don't know,it is impolite to light up a cigarette （香烟）without asking if it will disturb（打扰）them.At American restaurants and coffee shops you are usually served tap water before you order.You may find the bread and butter is free,and if you order coffee,you may get a free refill. Most cities and towns have no rules about opening and closing time for stores or restaurants,though they usually make rules for bars.Especially in large cities,stores may be open 24 hours a day.Serving in restaurants is often large；too large for many people.If you can't finish your meal but would like to enjoy the food later,ask your waitress or waiter for a "doggie bag".It may have a picture of a dog on it,but everybody knows you're taking the food for yourself.Supper and dinner are both words for the evening meal.Some people have "Sunday dinner".This is an especially big noon meal.Tips are not usually added to the check（支票）.They are not included in the price of the meal,either.A tip of about 15%is expected and you should leave it on the table when you leave.In some restaurants,a check is brought on a plate and you put your money there.Then the waiter or waitress brings you your change.36.Which statement is true？______A. American people like sitting with people they don't know.B. A hostess al ways seats a small group at a large table.C. American people never sit with people they don't know.D. American people would not light a cigarette if it will disturb others.37.What is served before you order？______A. Bread.B. Butter.C. Coffee.D. Cold water.38.What do American people always do when servings are too large for them？______A. They take the food home with a doggie bag for their dogs.B. They leave the food on the table and go away.C. They take the food home with a doggie bag and enjoy the food later.D. They ask the waitress or waiter to keep the food for them.39.Sunday dinner is ______ .A. a dinner in the eveningB. a big noon mealC. a big lunch on SundayD. a supper on Sunday40.If the price of the meal is ＄60，you should tip the waiter ______ in America.A. ＄15B. ＄9C. ＄3D. ＄1DFeb.17 should be the start of the spring semester for many middle and primary schools in China.However,to control the new coronavirus outbreak（新型冠状病毒），many schools delayed，following instructions from the Ministry of Education（MOE）.Students in China are still studying.Many students in Beijing and Guangzhou began their first day of online classes instead of having class at school on Feb 17.Students in Shanghai will start online classes on March 2."In the morning,I have English class.followed by Chinese and math,"Liu Bo,a junior 3 student from Beijing,told Xinhua"I have also learned about epidemic prevention（疫情防护）"According to the MOE，students are mainly taking classes to review previous knowledge rather than taking new classes during the online study period.Online courses are made up of epidemic prevention,psychological health（心理健康）and educational activities."Online courses are only temporary measures（暂时的措施）taken during the epidemic,so when the new semester begins,schools should not replace（代替）classroom teaching with online classes,"Lu Yugang from the ministry told China Daily.The ministry also called on schools not to increase their students' schoolwork burden（负担）.Schools should not ask students to study online for long periods of time or study things beyond（超出）their curriculum（课程）.Students must have enough time to rest,the ministry added.Also,it stressed that protecting students' eyesight must come first.41.Many Beijing students are taking online courses these days because ______ .A. it's more convenient to have class onlineB. Spring Festival is not finished yetC. they need more time to rest at homeD. it can help control the new coronavirus outbreak42.What's the meaning of the underlined word "delayed" in Paragraph 1？______A. 改变.B. 延迟.C. 重启.D. 庆祝.43.The online courses are made up of those except ______ .A. reviewing previous knowledgeB. taking new classesC. learning about infection preventionD. learning about psychological health44.What can we learn from Lu Yuyang ？______A. Online courses can't replace classroom teaching.B. Online courses will last for a long time.C. Online courses should not be used in the future.D. Online courses should be widely developed.45.Which one of the followings isn't mentioned（提及）in the passage？______A. When the online courses start.B. What the online courses teach.C. How to correctly provide online courses.D. How students have exams through online courses.四、单词拼写/单词释义（本大题共1小题，共10.0分）46.What will happen without forests？A lot of (1) （plant）will die and the animals will lose(2) （they）homes.In many places the new farmland will soon look like the olddeserts.Crops will not grow there.There won't be enough (3) （rainy），and the weather will get hot and dry. (4) the climate of the earth changes,life will be (5) （difficulty）for everyone.More and more rich farmland will (6) （appear）.We will suffer from both droughts（干旱）(7) flood.It is our duty to protect forests (8) （good）.Everyone should try his best to take care (9) forests.Stop (10) （cut）trees and make the world greener！五、书面表达（本大题共1小题，共15.0分）47.根据汉语提示，把下列短文翻译成英语小短文。
【最新】2019-2020学年深圳市宝安区七年级下期中考试数学试卷(有答案).doc
8
∴∠ 1＝∠ 2＝60° （等量代换） 又∵∠ ABD＝ 85°（已知） ∴∠ A＝ 180°﹣∠ ABD﹣∠ 1＝ 35°（三角形三内角和为 180°）， 故答案为： 同旁内角互补、 两直线平行； ∠ 3；两直线平行、 同位角相等； 对顶角相等； 等量代换； 35°． 21．【解答】解：∵ CD是 AB边上高， ∴∠ BDF＝ 90°， ∠ ABE＝∠ BFC﹣∠ BDF＝113°﹣ 90°＝ 23°， ∵ BE为角平分线， ∴∠ CBF＝∠ ABE＝ 23°， ∴∠ BCF＝ 180°﹣∠ BFC﹣∠ CBF＝ 44°． 22．【解答】解：当 a+b＝ 4， ab＝ 2 时， （ 1）原式＝ a2﹣ 2ab+b2 ＝ a2+2ab+b2﹣ 4ab ＝（ a+b） 2﹣ 4ab ＝ 16﹣ 4× 2 ＝8 （ 2）原式＝ a2+b2+2ab﹣2ab ＝（ a+b） 2﹣ 2ab ＝ 16﹣ 4 ＝ 12 23．【解答】解： （ 1）∵△ ABC是等边三角形， ∴ AB＝ AC，∠ B＝∠ PAC＝ 60°，
2019-2020 学年广东省深圳市宝安区七年级（下）期中数学试卷
一、选择题（每小题 3 分，共 36 分）
1．（3 分）下列计算正确的是（
）
A． a3?a2＝a6
B． a3﹣a2＝ a
C．（﹣ a3） 2＝ a6
D． a6÷ a2＝ a3
2．（3 分）下列各式中不能用平方差公式计算的是（
）
A．（ 2x+y）（ 2x﹣ y）
6．【解答】解：设第三边为 故选： C．
c，则 9+4＞ c＞ 9 ﹣ 4，即 13＞ c＞ 5．只有 9 符合要求．
2020年深圳市宝安区七下期末调研
2019-2020学年第二学期宝安区期末调研测试卷七年级 数学2017.07第一部分(选择题，共36分)一、选择题(本题共有12小题，每小题3分，共36分。
)1．计算12-的结果是（ ） 21.A 21.-B2.-C 2.D 2．下列图形中，是是轴对称图形的是（ ）3．人体中成熟个体红细胞的直径约为0．0000077米的细菌，将数据0．0000077用科学记数法表 示为（ ）A 、6107.7⨯B 、51077-⨯C 、6107.7-⨯D 、71077.0-⨯4．下列运算正确的是（ ）A ．623a a a =⋅B ．42833a a a =÷C ．()9322-=-x xD ．()933a a =5．下列事件中，随机事件是（ ）A 、任意一个三角形的内角和是180º；B 、打开电视，正在播出“亚冠”足球比赛；C 、通常情况下，向上抛出篮球，篮球会下落；D 、袋子中装有5个红球，摸出一个白球；6．如图1，已知直线a 、b 被直线c 所截，若a ∥b ，∠1=130º，则∠2的度数是（ ）A 、30ºB 、40ºC 、50ºD 、60º7．若有四根木棒，长度分别为4,5,6,9（单位：cm ），从中任意选取三根首尾顺次连接围成不同的三角形，下列不能围成三角形的是（ ）A ．4，5，6B ．4，6，9C ．5，6，9D ．4，5，98．在五张完全相同的卡片上，分别写有数字-2， -1， 0， 1， 2，现从中随机抽取一张，抽到写有正数的卡片的概率是（ ）A 、51B 、52C 、53D 、549．某天小明骑自行车上学，途中因自行车发生故障，修车耽误了一段时间后继续骑行，按时赶到了学校。
如图2中描述了他上学的途中离家距离S（米）与离家时间t（分钟）之间的函数关系，下列说法中正确的个数是（）⑴中途修成时间为5分钟；⑵到达学校时共用时间20分钟；⑶学校离家的距离为2000米；⑷修车后的骑行平均速度是修车前平均速度的2倍；A、1个B、2个C、3个D、4个10．如图3，点E、F在AC上，AE=CF，∠A=∠C，添加下列条件后仍不能使△ADF≌△CBE的是（）A、DF=BEB、∠D=∠BC、AD=CBD、∠AFD=∠CEB 图311．如图4，边长为（a+2）的正方形纸片剪出一个边长为a的正方形之后，剩余部分可剪拼成一个长方形（不重叠无缝隙），若拼成的长方形一边长为2，则另一边长是（）A．2 B．2a+4 C．2a+2 D．4a+412．如图5，BE⊥AE，CF⊥AE，垂足分别为E、F，D是EF的中点，CF=AF。
2020~2021学年广东深圳宝安区初一下学期期末英语试卷-学生用卷
2020~2021学年广东深圳宝安区初一下学期期末英语试卷-学生用卷一、完成句子（本大题共2小题，每小题1分，共2分）1、【来源】 2020~2021学年广东深圳宝安区初一下学期期末第19题1分翻译。
你想知道Daisy多久参加一次学校旅行，你问Daisy：2、【来源】 2020~2021学年广东深圳宝安区初一下学期期末第20题1分翻译。
你想知道Daisy对学校旅行的看法，你问Daisy：二、选择题（本大题共10小题，每小题0.5分，共5分）3、【来源】 2020~2021学年广东深圳宝安区初一下学期期末第21题0.5分—Why do you like reading books by Lu Xun?—Because his books always encourage me to study hard.A. give…a lot of hopeB. make…feel sadC. make…feel moved4、【来源】 2020~2021学年广东深圳宝安区初一下学期期末第22题0.5分—More and more people are willing to be volunteers in Shenzhen.—Helping those in need is a valuable experience for them.A. boring and helplessB. useful and importantC. simple and useless5、【来源】 2020~2021学年广东深圳宝安区初一下学期期末第23题0.5分—Do you know anything about Alzheimer disease （阿尔茨海默病）?—Yes, I do. People with the disease always forget things.A. cannot rememberB. do not wantC. cannot plan6、【来源】 2020~2021学年广东深圳宝安区初一下学期期末第24题0.5分—Many people do not like playing with Tom because he is foolish.—I don't think so. In my opinion, Tom is an interesting boy.A. smartB. funnyC. stupid7、【来源】 2020~2021学年广东深圳宝安区初一下学期期末第25题0.5分—A lot of animals are in danger now.—What bad news! All of us should take action to take care of animals.A. look aroundB. look likeC. look after8、【来源】 2020~2021学年广东深圳宝安区初一下学期期末第26题0.5分—Tom, will you take your foreign teachers to travel in Bao'an?—Sure. We just making a travelling plan. We will go tomorrow.A. allowedB. finishedC. practiced9、【来源】 2020~2021学年广东深圳宝安区初一下学期期末第27题0.5分—Never give up, Tim. You can your dream if you work hard.—Thank you, Miss Chen. I'll try my best.A. preferB. forgetC. achieve10、【来源】 2020~2021学年广东深圳宝安区初一下学期期末第28题0.5分—Amy, would you like to help us protect water?—Yes, I'd like to. I think I can do well because I work in a club for saving water.A. rushed toB. used toC. disagreed to11、【来源】 2020~2021学年广东深圳宝安区初一下学期期末第29题0.5分—Ben, you can't always depend on me. You should learn to look after yourself.—Yes, mum. I will try doing something.A. by myselfB. with your helpC. all day and all night12、【来源】 2020~2021学年广东深圳宝安区初一下学期期末第30题0.5分—What weather! Let's go camping on the coast.—I'd like to. But the epidemic（疫情） is still serious. We had better stay at home.A. terribleB. badC. perfect三、完形填空（本大题共10小题，每小题1分，共10分）13、【来源】 2020~2021学年广东深圳宝安区初一下学期期末第31~40题10分Reading a poem is enjoyable. Every now and then when you learn a poem, it attracts you and you just have to set it to memory. You want to live with it and1its wonderful lineswith others. Many people like poems and want to learn poems. However, how do you begin to memorize （背记）2?It's quite3: just start at the beginning and memorize the poem line by line. It's not as difficult as you think. Some poems may be harder than others, andthe4the poem is, the more time it will take to memorize it. Don't worry about that and take your time to really enjoy the process and5the hidden（隐藏的）meaning within the poem.When you are6to memorize a poem with your own understanding, you will find it is worth the effort（努力）. Let's look at the process of7 a poem.8, you need to read the poem over, slowly and aloud. Then you canuse9or a piece of paper to cover everything but the first line of the poem. Read it. Look away and say it. Repeat until you've got it. Do the same to the rest of the lines. In addition,to understand the whole poem, you can know every word's meaning first because a poem is made up of different10. Finally after you are familiar with a poem in this way, you can memorize it well.A. shareB. writeC. reciteD. copyA. lettersB. passagesC. booksD. poemsA. difficultB. helpfulC. simpleD. harmfulA. shorterB. longerC. betterD. worseA. rememberB. forgetC. overlookD. understandA. likelyB. unableC. comfortableD. ableA. writingB. memorizingC. reportingD. readingA. LastlyB. ThenC. First of allD. SecondA. a cardB. a ringC. an eraserD. a keyA. wordsB. rhymesC. linesD. verses四、阅读理解（本大题共15小题，每小题2分，共30分）14、【来源】 2020~2021学年广东深圳宝安区初一下学期期末（A篇）第41~45题10分Do you like drinking tea? I like it very much, so I want to tell you something about a kind of famous tea.(1) How much should Tom pay if he buys 200 grams of Biluochun?A. About 130-150 yuan.B. About 780-900 yuan.C. About 260-300 yuan.D. About 520-600 yuan.(2) What can we learn about Biluochun?A. Its shape is like a snail.B. It is a kind of black tea.C. It has a history of less than 1, 000 years.D. It can help people fall asleep much more easily.(3) Who may be interested in this poster?A. Emma—She is over-weighed.B. Cindy—She often feels excited.C. Lucy—She is thin and short.D. Dennis—He likes watching snails.(4) What should we know when we buy Biluochun?①the fragrance of the tea②the time the fragrance lasts③the color of the tea water④the long history of the teaA. ①②④B. ①③④C. ①②③D. ②③④(5) Why does the writer make this poster?A. To teach people how to make tea.B. To show his interest in drinking tea.C. To encourage people to buy Biluochun.D. To tell people something about Biluochun.15、【来源】 2020~2021学年广东深圳宝安区初一下学期期末（B篇）第46~50题10分The Nature Education Center at Shenzhen Bay Park in Futian District reopened to the public on the Saturday before June 1, the Children's Day.There are six education centers in total in Shenzhen. The center in Futian District is the first nature education center to reopen after coronavirus closure. It is open from 2 p.m. to 4 p.m., Wednesday to Sunday. The center only allows 20 people at a time to visit for social distancing.As the city is becoming safer during the pandemic, many parks have been reopened with strict prevention measures（预防措施）. And the parks have taken action to make sure a clean and safe environment for children.Shenzhen Children's Paradise Park in Futian District is ready for children to visit during the Children's Day this year. But the park limits the number of visitors to 20, 000 and will stop selling tickets once the limit is met.Xiangmi Park and the Dasha River Ecological Corridor are also good places for children and parents to enjoy outdoor activities on Children's Day.(1) What does the underlined word "closure" in Paragraph 2 probably mean?A. the opening once againB. the closing for a timeC. the reopening to the publicD. the shutting down forever(2) When can we visit the Nature Education Center?A. At 3 p.m. Saturday.B. At 3 p.m. Monday.C. At 5 p.m. Sunday.D. At 1 p.m. Thursday.(3) Why does the center only allow 20 people to enter at a time?A. It is not big enough for more people.B. Visitors need to keep social distancing.C. People don't know it's been reopened.D. Few people are interested in the center.(4) Which of the following is the main idea of the passage?A. The parks limit the number of visitors to 20, 000.B. The parks have very strict prevention measures.C. The workers can also have fun in Xiangmi Park.D. Parks in Futian District are reopening for children.(5) In which page of the newspaper can we find this passage?A. Person.B. Food.C. Sports.D. Local.16、【来源】 2020~2021学年广东深圳宝安区初一下学期期末（C篇）第51~55题10分Electric cars are cars that use electricity for power. They have anelectric motor which is powered by batteries or a fuel cell.There are different kinds of electric cars. Plug-in hybrids use both fossil fuel and battery. The battery of plug-in hybrids can be recharged（充电）. The second kind of electric cars is battery electric cars. It does not use any fuel. However, people can still drive it because it runs only on electricity. Another kind of electric cars are hydrogen（氢气）fuel cars. The power of it comes from hydrogen gas. When people are driving the cars, the hydrogen gas will help the battery make electricity.Electric cars produce less pollution than the most efficient conventional（传统的）cars. In other words, they are greener and more useful for protecting environment. Now more and more people are interested in electric cars. However, electric cars are not cheap, and sometimes you would even spend more money buying electric cars. Therefore, governments in some cities like Dongguan, Shenzhen and Guangzhou have taken action to encourage people to buy electric cars by giving them money in other ways.With electric cars becoming more and more popular, hopefully the environment will be greatly improved.(1) Which of the following do electric cars use for power?A. Solar power.B. Wind.C. Water.D. Electricity.(2) What kind of cars use both fossil fuel and battery?A. Hydrogen fuel cars.B. Plug-in hybrids.C. Battery electric cars.D. Fossil fuel cars.(3) Why do governments encourage people to buy electric cars?A. There are too many electric cars on sale.B. Electric cars are good for the environment.C. They want to get more money from people.D. The conventional cars are much more expensive.(4) What can we infer from the passage?A. Hydrogen can help all kinds of cars make electricity.B. Electric cars can solve all the environmental problems.C. More and more people will buy electric cars in the future.D. People don't want to buy electric cars because of the price.(5) What is the best title for the passage?A. Electric carsB. Fossil fuel carsC. Cars and environmentD. Cars and recharging五、六选五（本大题共5小题，每小题1分，共5分）17、【来源】 2020~2021学年广东深圳宝安区初一下学期期末第56~60题5分以下是一篇短文，请阅读全文，并从下列方框里的六个句子中选择五个还原到原文中，使原文意思完整、连贯。
2020年深圳市宝安区七下期末考试
2019-2020学年广东省深圳市宝安区七年级（下）期末数学试卷一、选择题：每小题3分，共36分，每小题有四个选项，其中只有一个是正确的，请把答案按要求填涂到答题卡相应位置上．1．（3分）计算（﹣1）0的结果为（）A．1 B．﹣1 C．0 D．±12．（3分）下面有4个汽车标志图案，其中是轴对称图形的有（）A．1个 B．2个 C．3个 D．4个3．（3分）环境监测中PM2.5是大气压中直径小于或等于0.0000025米的颗粒物，将数据0.0000025用科学记数法表示为（）A．0.25×10﹣5B．2.5×10﹣6C．2.5×10﹣5D．25×10﹣74．（3分）下列事件中，确定事件是（）A．﹣a一定是负数B．抛掷1个均匀的骰子，出现6点向上C．两条直线被第三条直线所截，同位角相等D．通常情况下，抛掷一石头，石头终将落地5．（3分）下列运算正确的是（）A．﹣5（a﹣1）=﹣5a+1 B．2a3÷a2=2a C．3a3•2a2=6a6D．（x﹣3）（x+2）=x2﹣66．（3分）如图，下列推理错误的是（）A．∵∠1=∠2，∴c∥d B．∵∠3=∠4，∴c∥d C．∵∠1=∠3，∴a∥b D．∵∠1=∠4，∴a∥b7．（3分）对任意整数n，按下列程序计算，该输出答案为（）A．n B．n2C．2n D．18．（3分）小明的父母出去散步，从家走了20分钟到一个离家900米的报亭，母亲随即按原速返回，父亲看了10分钟报纸后，用了15分钟返回家，下面的图形中表示父亲离家的时间（分钟）与距离（米）之间的关系是（）A．B．C．D．9．（3分）如图，用直尺和圆规作一个已知角的平分线，能得出∠MOC=∠NOC 的依据是（）A．SSS B．SAS C．ASA D．AAS10．（3分）如图所示，已知AB=DB，∠ABD=∠CBE，添加下列哪一个条件后，仍不能证明△ABC≌△DBE的是（）A．DE=AC B．∠BDE=∠BAC C．∠DEB=∠ACB D．BE=BC11．（3分）如图，在△ABC中，AB=AC，AB的垂直平分线DE交AC于点D，交AB于点E，已知AB=12，△DBC的周长为20，则底边BC的长是（）A．14 B．12 C．8 D．612．（3分）如图，将图1中阴影部分拼成图2，根据两个图形中阴影部分的关系，可以验证下列哪个计算公式（）A．（a+b）（a﹣b）=a2﹣b2B．（a﹣b）2=a2﹣2ab+b2C．（a+b）2=a2+2ab+b2D．（a+b）2=（a﹣b）2+4ab二、填空题：每小题3分，共12分，请把答案填到答案卷相应位置上．13．（3分）计算：3a（b﹣1）=．14．（3分）若把如图所示网格设计成一个投镖靶子，使得随意投掷一次飞镖击中红色区域的概率为，那么需要在网格中涂成红色的小正方形的个数为．15．（3分）如图，是用棋子摆成的图形，按照这种摆法，第n个图形中所需棋子的总数是用了．16．（3分）如图，AD是△ABC的角平分线，DE⊥AC，垂足是E，BF∥AC交ED=39，则EF=．的延长线于F点．若BC恰好平分∠ABF，且AB=13，S△ABD三、解答题：第17题10分，第18，19每题6分，第20，21每题8分，第22题5分，第23题9分，共52分．17．（10分）计算：（1）﹣23+（π﹣3）0+（）﹣1÷；（2）（﹣2x3）2•（2x）3+（﹣3x3）3．18．（6分）先化简，后求值：[（x+2y）（x﹣2y）+4（x﹣y）2]÷4x，其中x=，y=﹣1．19．（6分）甲袋里装有红球5个，白球2个和黑球12个，乙袋里装有红球20个，白球20个和黑球10个．（1）如果你取出1个黑球，选哪个袋子成功的机会大？请说明理由．（2）某同学说“从乙袋取出10个红球后，乙袋中的红球个数仍比甲袋中红球个数多，所以此时想取出1个红球，选乙袋成功的机会大．”你认为此说法正确吗？为什么？20．（8分）如图，P、A、B在一条直线上．（1）尺规作图，以P为顶点，以射线PB为一边，作∠QPB=∠CAB；（不写作法，保留作图痕迹）（2）若∠CAB=45°，判断AC与PQ的位置关系，并说明理由．21．（8分）小明、小亮从宝安中心图书馆出发，沿相同的线路跑向宝安体育场，小明先跑一点路程后，小亮开始出发，当小亮超过小明150米时，小亮停在此地等候小明，两人相遇后，一起以小明原来的速度跑向宝安体育场，如图，反映了两人所跑路程y（米）与所用时间x（秒）之间的关系，请根据题意解答下列问题：（1）问题中的自变量是，因变量是；（2）小明共跑了米，小明的速度为米/秒；（3）图中a=米，小亮在途中等候小明的时间是秒；（4）小亮从A跑到B这段的速度为米/秒．22．（5分）如图，四边形ABCD为一长方形纸片，AD∥BC，∠DAB=∠ABC=∠C=∠ADC=90°，E为BC上一点，将纸片沿AE折叠，B点落在长方形外的F点，连BD，若∠CBD=20°，且AF∥BD．求∠BAE的度数？解∵AD∥BC，∠CBD=20°（已知）∴∠ADB=∠CBD=20°（）∵AF∥BD（已知）∴∠ADB=（两直线平行，内错角相等）∵∠DAB=90°（已知）∴∠BAF=∠DAB+∠ADF=°∵纸片沿AE折叠∴∠BAE=∴∠BAE=∠BAF=．23．（9分）在△ABC中，AB=AC，点D是直线BC上一点（不与B、C重合），以AD为一边在AD的右侧作△ADE，使AD=AE，∠DAE=∠BAC，连接CE．（1）如图1，当点D在直线BC上，如果∠BAC=90°，求证：CE+DC=BC证明：∵∠BAC=∠DAE（已知）∴∠BAC﹣∠DAC=∠DAE﹣∠DAC即∠BAD=∠CAE在△ABD与△ACE中，∴△ABD≌△（）∴（全等三角形的对应法相等）∵BD+DC=BC∴CE+DC=BC．（2）如图1，在（1）条件下，求：∠BCE的度数？（3）如图2，当点D在线段BC上移动，设∠BAC=α，∠BCE=β，则α，β之间有怎样的数量关系？请说明理由．2019-2020学年广东省深圳市宝安区七年级（下）期末数学试卷参考答案与试题解析一、选择题：每小题3分，共36分，每小题有四个选项，其中只有一个是正确的，请把答案按要求填涂到答题卡相应位置上．1．（3分）计算（﹣1）0的结果为（）A．1 B．﹣1 C．0 D．±1【分析】根据非零的零次幂等于1，可得答案．【解答】解：（﹣1）0=1，故选：A．2．（3分）下面有4个汽车标志图案，其中是轴对称图形的有（）A．1个 B．2个 C．3个 D．4个【分析】根据轴对称图形的概念结合4个汽车标志图案的形状求解．【解答】解：由轴对称图形的概念可知第1个，第2个，第3个都是轴对称图形．第4个不是轴对称图形，是中心对称图形．故是轴对称图形的有3个．故选：C．3．（3分）环境监测中PM2.5是大气压中直径小于或等于0.0000025米的颗粒物，将数据0.0000025用科学记数法表示为（）A．0.25×10﹣5B．2.5×10﹣6C．2.5×10﹣5D．25×10﹣7【分析】绝对值小于1的正数也可以利用科学记数法表示，一般形式为a×10﹣n，与较大数的科学记数法不同的是其所使用的是负指数幂，指数由原数左边起第一个不为零的数字前面的0的个数所决定．【解答】解：将数据0.0000025用科学记数法表示为2.5×10﹣6，故选：B．4．（3分）下列事件中，确定事件是（）A．﹣a一定是负数B．抛掷1个均匀的骰子，出现6点向上C．两条直线被第三条直线所截，同位角相等D．通常情况下，抛掷一石头，石头终将落地【分析】根据事件发生的可能性大小判断相应事件的类型即可．【解答】解：A、﹣a是负数、零是随机事件，故A不符合题意；B、抛掷1个均匀的骰子，出现6点向上是随机事件，故B不符合题意；C、两条直线被第三条直线所截，同位角相等是随机事件，故C不符合题意；D、通常情况下，抛掷一石头，石头终将落地是必然事件，故D符合题意；故选：D．5．（3分）下列运算正确的是（）A．﹣5（a﹣1）=﹣5a+1 B．2a3÷a2=2a C．3a3•2a2=6a6D．（x﹣3）（x+2）=x2﹣6【分析】根据单项式乘以多项式、单项式除以单项式、多项式乘以多项式分别求出每个式子的值，再判断即可．【解答】解：A、结果是﹣5a+5，故本选项不符合题意；B、结果是2a，故本选项符合题意；C、结果是6a5，故本选项不符合题意；D、结果是x2﹣x﹣6，故本选项不符合题意；故选：B．6．（3分）如图，下列推理错误的是（）A．∵∠1=∠2，∴c∥d B．∵∠3=∠4，∴c∥d C．∵∠1=∠3，∴a∥b D．∵∠1=∠4，∴a∥b【分析】A、根据内错角相等，两直线平行进行判定；B根据同位角相等，两直线平行进行分析；C中∠1，∠3不是同位角，也不是内错角，因此不能判定直线平行；D根据内错角相等，两直线平行进行判定．【解答】解：A、∵∠1=∠2，∴c∥d，正确，不符合题意；B、∵∠3=∠4，∴c∥d，正确，不符合题意；C、∵∠1=∠3，∴a∥b，错误，符合题意；D、∵∠1=∠4，∴a∥b，正确，不符合题意；故选：C．7．（3分）对任意整数n，按下列程序计算，该输出答案为（）A．n B．n2C．2n D．1【分析】根据题中的程序框图列出关系式，化简即可得到结果．【解答】解：（n2+n）÷n﹣n=n+1﹣n=1．故选：D．8．（3分）小明的父母出去散步，从家走了20分钟到一个离家900米的报亭，母亲随即按原速返回，父亲看了10分钟报纸后，用了15分钟返回家，下面的图形中表示父亲离家的时间（分钟）与距离（米）之间的关系是（）A．B．C．D．【分析】根据函数图象的横坐标，可得时间，根据函数图象的纵坐标，可得离家的距离．【解答】解：20分钟到报亭离家的距离随时间的增加而增加，看报10分钟，离家的距离不变；15分钟回家离家的距离岁时间的增加而减少，故D符合题意．故选：D．9．（3分）如图，用直尺和圆规作一个已知角的平分线，能得出∠MOC=∠NOC 的依据是（）A．SSS B．SAS C．ASA D．AAS【分析】根据角平分线的作法可知MO=NO，CO=CO，MC=NC，符合三角形全等的判定方法中的SSS，可证△OMC≌△ONC，即证∠MOC=∠NOC．【解答】解：如图：由作法知在△COM和△CNO中，，∴△OMC≌△ONC（SSS），∴∠MOC=∠NOC．10．（3分）如图所示，已知AB=DB，∠ABD=∠CBE，添加下列哪一个条件后，仍不能证明△ABC≌△DBE的是（）A．DE=AC B．∠BDE=∠BAC C．∠DEB=∠ACB D．BE=BC【分析】利用∠ABD=∠CBE，加上∠ABC=∠DBE，则利用全等三角形的判定方法对各选项进行判断．【解答】解：∵∠ABD=∠CBE，∴∠ABC=∠DBE，∵AB=DB，∴BC=BE时，可利用“SAS”判定△ABC≌△DBE；当∠BDE=∠BAC时，可利用“ASA”判定△ABC≌△DBE；当∠DEB=∠ACB时，可利用“AAS”判定△ABC≌△DBE．故选：A．11．（3分）如图，在△ABC中，AB=AC，AB的垂直平分线DE交AC于点D，交AB于点E，已知AB=12，△DBC的周长为20，则底边BC的长是（）A．14 B．12 C．8 D．6【分析】由AB的中垂线DE交AC于点D，交AB于点E，可得AD=BD，又由AB=12，△DBC的周长为20，可求得BC的长．【解答】解：∵AB的中垂线DE交AC于点D，交AB于点E，∵△DBC的周长为20，∴BC+CD+BD=BC+CD+AD=BC+AC=20，∵AB=12，∴AC=12．∴BC=8，故选：C．12．（3分）如图，将图1中阴影部分拼成图2，根据两个图形中阴影部分的关系，可以验证下列哪个计算公式（）A．（a+b）（a﹣b）=a2﹣b2B．（a﹣b）2=a2﹣2ab+b2C．（a+b）2=a2+2ab+b2D．（a+b）2=（a﹣b）2+4ab【分析】根据图形确定出图1与图2的面积，即可作出判断．【解答】解：根据题意得：（a﹣b）2=a2﹣2ab+b2，故选：B．二、填空题：每小题3分，共12分，请把答案填到答案卷相应位置上．13．（3分）计算：3a（b﹣1）=ab﹣3a．【分析】单项式与多项式相乘的运算法则：单项式与多项式相乘，就是用单项式去乘多项式的每一项，再把所得的积相加．依此即可求解．【解答】解：3a（b﹣1）=ab﹣3a．故答案为：ab﹣3a．14．（3分）若把如图所示网格设计成一个投镖靶子，使得随意投掷一次飞镖击中红色区域的概率为，那么需要在网格中涂成红色的小正方形的个数为6．【分析】直接利用几何概率公式得出涂成红色的小正方形的个数．【解答】解：∵随意投掷一次飞镖击中红色区域的概率为，总数为16个正方形，∴在网格中涂成红色的小正方形的个数为：6．故答案为：6．15．（3分）如图，是用棋子摆成的图形，按照这种摆法，第n个图形中所需棋子的总数是用了n（n+1）个．【分析】观察每个图形中棋子的个数的规律即可发现有关棋子个数的通项公式，从而得到答案．【解答】解：第一个图形中有1×2=2个棋子，第二个图形中有2×3=6个棋子，第三个图形中有3×4=12个棋子，…故第n个图形中所需棋子的总数是用了n（n+1）个．故答案为：n（n+1）个．16．（3分）如图，AD是△ABC的角平分线，DE⊥AC，垂足是E，BF∥AC交ED=39，则EF=12．的延长线于F点．若BC恰好平分∠ABF，且AB=13，S△ABD【分析】过D作DG⊥AB于G，根据角平分线的性质得到DE=DG，根据平行线的性质得到∠F=90°，得到DF=DG，求得EF=2DG，根据三角形的面积得到DG=6，于是得到结论．【解答】解：过D作DG⊥AB于G，∵AD是△ABC的角平分线，DE⊥AC，∴DE=DG，∵BF∥AC，∴∠F+∠DEA=180°，∴∠F=90°，∴DF=DG，∴EF=2DG，∵AB=13，S=39，△ABD∴DG=6，∴EF=12，故答案为：12．三、解答题：第17题10分，第18，19每题6分，第20，21每题8分，第22题5分，第23题9分，共52分．17．（10分）计算：（1）﹣23+（π﹣3）0+（）﹣1÷；（2）（﹣2x3）2•（2x）3+（﹣3x3）3．【分析】（1）首先计算乘方、零次幂、负整数指数幂，然后再计算除法，最后计算加减即可；（2）首先计算乘方，然后再计算乘法，最后合并同类项即可．【解答】解：（1）原式=﹣8+1+2×4=﹣8+1+8=1；（2）原式=4x6•8x3﹣27x9=32x9﹣27x9=5x9．18．（6分）先化简，后求值：[（x+2y）（x﹣2y）+4（x﹣y）2]÷4x，其中x=，y=﹣1．【分析】根据整式的运算法则即可求出答案．【解答】解：当x=，y=﹣1时，∴原式=[x2﹣4y2+4（x2﹣2xy+y2）]÷4x=（x2﹣4y2+4x2﹣8xy+4y2）÷4x=（5x2﹣8xy）÷4x=x﹣2y=×﹣2×（﹣1）=2+2=419．（6分）甲袋里装有红球5个，白球2个和黑球12个，乙袋里装有红球20个，白球20个和黑球10个．（1）如果你取出1个黑球，选哪个袋子成功的机会大？请说明理由．（2）某同学说“从乙袋取出10个红球后，乙袋中的红球个数仍比甲袋中红球个数多，所以此时想取出1个红球，选乙袋成功的机会大．”你认为此说法正确吗？为什么？【分析】（1）利用小球个数，直接利用概率公式计算得出答案；（2）利用小球个数，直接利用概率公式计算得出答案．【解答】解：（1）∵甲袋里装有红球5个，白球2个和黑球12个，∴取出1个黑球的概率为：=；∵乙袋里装有红球20个，白球20个和黑球10个，∴取出1个黑球的概率为：=；∵＞，∴取出1个黑球，选甲袋子成功的机会大；（2）说法错误，理由：∵从乙袋取出10个红球后，乙袋中的红球个数为10，∴此时从乙袋中摸到红球的概率为：，从甲袋中摸到红球的概率为：，∴＞，∴选甲袋成功的机会大．20．（8分）如图，P、A、B在一条直线上．（1）尺规作图，以P为顶点，以射线PB为一边，作∠QPB=∠CAB；（不写作法，保留作图痕迹）（2）若∠CAB=45°，判断AC与PQ的位置关系，并说明理由．【分析】（1）根据作一个角等于已知角的方法作图即可；（2）图1，根据同位角相等两直线平行可得AC∥PQ；图2，根据三角形内角和为180°可推出AC⊥PQ．【解答】解：（1）如图所示：（2）图1，AC∥PQ，∵∠QPB=∠CAB，∴PQ∥AC；如图2，AC⊥PQ，延长CA交PQ于点M，∵∠QPB=∠CAB=45°∴∠PAM=45°，∴∠PMA=180°﹣45°﹣45°=90°，∴AC⊥PQ．21．（8分）小明、小亮从宝安中心图书馆出发，沿相同的线路跑向宝安体育场，小明先跑一点路程后，小亮开始出发，当小亮超过小明150米时，小亮停在此地等候小明，两人相遇后，一起以小明原来的速度跑向宝安体育场，如图，反映了两人所跑路程y（米）与所用时间x（秒）之间的关系，请根据题意解答下列问题：（1）问题中的自变量是所用时间x，因变量是两人所跑路程y；（2）小明共跑了900米，小明的速度为 1.5米/秒；（3）图中a=米，小亮在途中等候小明的时间是100秒；（4）小亮从A跑到B这段的速度为 2.5米/秒．【分析】（1）根据题意即可得到结论；（2）终点D的纵坐标就是路程，横坐标就是时间；（3）首先求得C点对用的横坐标，即a的值，则CD段的路程可以求得，时间是560﹣500=60秒，则小亮跑步的速度即可求得；B点时，所用的时间可以求得，然后求得路程是150米时，小明用的时间，就是小亮出发的时刻，两者的差就是所求；（4）根据题意即可得到结论．【解答】解：（1）问题中的自变量是所用时间x，因变量是两人所跑路程y；（2）根据图象可以得到：小明共跑了900米，用了600秒，则速度是：900÷600=1.5米/秒；（3）过B作BE⊥x轴于E．小明跑500秒的路程是a=500×1.5=750米，小明跑600米的时间是（750﹣150）÷1.5=400秒，小亮在途中等候甲的时间是500﹣400=100秒．（4）小亮跑步的速度是750÷（400﹣100）=2.5米/秒，答案为：所用时间x，两人所跑路程y，900，1.5，100，2.5．22．（5分）如图，四边形ABCD为一长方形纸片，AD∥BC，∠DAB=∠ABC=∠C=∠ADC=90°，E为BC上一点，将纸片沿AE折叠，B点落在长方形外的F点，连BD，若∠CBD=20°，且AF∥BD．求∠BAE的度数？解∵AD∥BC，∠CBD=20°（已知）∴∠ADB=∠CBD=20°（两直线平行，内错角相等）∵AF∥BD（已知）∴∠ADB=∠FAG（两直线平行，内错角相等）∵∠DAB=90°（已知）∴∠BAF=∠DAB+∠ADF=110°∵纸片沿AE折叠∴∠BAE=∠FAE∴∠BAE=∠BAF=55°．【分析】根据平行线的性质，即可得到∠FAG=20°，进而得到∠BAF的度数，再根据轴对称的性质，即可得到∠BAE=∠BAF=55°．【解答】解∵AD∥BC，∠CBD=20°，（已知）∴∠ADB=∠CBD=20°，（两直线平行，内错角相等）∵AF∥BD，（已知）∴∠ADB=∠FAG，（两直线平行，内错角相等）∵∠DAB=90°，（已知）∴∠BAF=∠DAB+∠ADF=110°，∵纸片沿AE折叠，∴∠BAE=∠FAE，∴∠BAE=∠BAF=55°．故答案为：两直线平行，内错角相等，∠FAG，110，∠FAE，55°．23．（9分）在△ABC中，AB=AC，点D是直线BC上一点（不与B、C重合），以AD为一边在AD的右侧作△ADE，使AD=AE，∠DAE=∠BAC，连接CE．（1）如图1，当点D在直线BC上，如果∠BAC=90°，求证：CE+DC=BC证明：∵∠BAC=∠DAE（已知）∴∠BAC﹣∠DAC=∠DAE﹣∠DAC即∠BAD=∠CAE在△ABD与△ACE中，∴△ABD≌△ACE（SAS）∴BD=CE（全等三角形的对应法相等）∵BD+DC=BC∴CE+DC=BC．（2）如图1，在（1）条件下，求：∠BCE的度数？（3）如图2，当点D在线段BC上移动，设∠BAC=α，∠BCE=β，则α，β之间有怎样的数量关系？请说明理由．【分析】（1）根据全等三角形的判定方法，补充条件即可解决问题；（2）由∠BAC=90°，AB=AC，推出∠B=45°，由△ABD≌△ACE，推出∠ACE=∠B=45°即可解决问题（3）由∠BAC=α，AB=AC，推出∠B=（180°﹣α）=90°﹣α．，由△ABD≌△ACE，推出∠ACE=∠B即可解决问题．【解答】解：（1）：∵∠BAC=∠DAE（已知）∴∠BAC﹣∠DAC=∠DAE﹣∠DAC即∠BAD=∠CAE在△ABD与△ACE中，，∴△ABD≌△ACE（SAS）∴BD=CE（全等三角形的对应法相等）∵BD+DC=BC∴CE+DC=BC．故答案为ACE，SAS，BD=CE．（2）∵∠BAC=90°，AB=AC，∴∠B=45°，∵△ABD≌△ACE，∴∠ACE=∠B=45°．∴∠BCE=90°．（3）∵∠BAC=α，AB=AC，∴∠B=（180°﹣α）=90°﹣α．，∵△ABD≌△ACE，∴∠ACE=∠B∴β=2（90°﹣α），即α+β=180°．。