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先化简,再求值:÷(x+1﹣),其中x=﹣2.
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先化简再求值23x+11-3x+x-22+x其中x=2.
.先化简再求值xx﹣1+2xx+1﹣3x﹣12x﹣5其中x=2.
先化简再求值x+5x﹣1+x﹣22其中x=﹣2.
先化简再求值2x+y2x﹣y﹣32x﹣y2其中x=﹣1y=2.
先化简再求值3x﹣y2+3x+y3x﹣y其中x=1y=﹣2.
先化简再求值﹣35x2+xy+2x2+xy﹣1其中x=﹣1y=﹣2.
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先化简再求值xx-1+2xx+1-3x-12x-5其中x=2.
先化简再求值x+22﹣x+1x﹣1其中x=﹣1/2.
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先化简再求值x2x﹣3﹣xx2﹣x﹣1其中x=﹣2.
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先化简再求值2x+7+3x-2其中x=2.
先化简再求值2x+1x﹣1﹣x2x﹣1其中x=﹣2.
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先化简再求值﹣•x﹣1其中x=2.
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QuestionMyninth﹣gradeartteacherdoesn'tgiveanygradeabove94%becauseshesaysThere'salwaysroomforimprovement.InpreviousyearsIearneda99%anda100%.The94%IreceivedthistermdoesnotreflectthehardworkthatIputintothiscourse.BecauseofherimprovementtheoryIgotalowergradethanIdeserve.Ishergradingphilosophymorallycorrect AnswerYourteacher'sgradingsystemmaybeunwisebutitisnotmorallywrong.Ateacherdeserveswidelatitudeinselectingthemethodofgradingthatbestpromoteslearninginherclassroomthatisafteralltheprimefunctionofgrades.Itisshewhohasthetrainingandexperiencetomakethisdecision. Youcancriticizehermethodology.A100neednotimplythatthereisnopossibilityofimprovementonlythatastudentsuccessfullycompletedthecoursework.Aninthgradercouldgetawell﹣earned100inEnglishclassbutstillhasawaytogobeforehewritesaswellasJaneAusten.What'smoregradesarenotonlyaneducationaldevicebutarealsopartofascreeningsystemtohelpassign分配kidstotheirnextclassorprogram.Bycappinghergradesat94whilemostotherteachersgradeonascalethattopsoutat100yourteachercouldriskmakingastudentloseachanceofgettingascholarshiporgettingintoatopcollege. Whatitiswrongtocondemnherforisoverlookingyourhardwork.Yourhardworkisworthyofencouragementbuteffortdoesnotequalaccomplishment.IfscholarssuddenlydiscoveredthatRembrandthaddashedoffTheNightWatchinanafternoonitwouldstillbeTheNightWatch. IcouldspendmonthssweatingovermyownpaintingsbutI'dproducesomethingyouwouldn'twanttohanginyourlivingroomoryourgarage. Onefeatureofagoodgradingsystemisthatthosemeasuredbyitgenerallyregarditasfairandreasonable﹣notthecasehere.Strongfeelingofangerisseldomanaidtoeducation.Andsoyournextstepshouldbetodiscussyourconcernswithyourteacherortheprincipal. 1Whenwritingthequestiontheninth﹣graderwas. A.annoyed B.worried C.excited D.delighted 2TheunderlinedwordlatitudeinParagraph2probablymeans. A.difference B.knowledge C.freedom D.experience 3Rembrandt'spaintingismentionedtoshowthat. A.there'sdifferencebetweeneffortandachievement B.TheNightWatchwascompletedinhalfaday C.everybody'shardworkshouldbeencouraged D.oneistoblamefordoingtheworkinahurry 4Whatistheauthor'sattitudetowardsthegradingsystemoftheninth﹣grader'steacher A.Supportive. B.Confused. C.Unconcerned. D.Unfavorable.
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DearDad TodayIwasattheshoppingmallandIspentalotoftimereadingtheFather'sDaycards.TheyallhadaspecialmessagethatinsomewayoranotherreflectedhowIfeelaboutyou.YetasIselectedandreaditoccurredtomethatnotasinglecardsaidwhatIreallywanttosaytoyou. You'llsoonbe84yearsoldDadandyouandIwillhavehad55Father'sDaystogether.Ihaven'talwaysbeenwithyouonFather'sDaybutI'vealwaysbeenwithyouinmyheart. YouknowDadtherewasatimewhenwewereseparatedbythegenerationgap.YoustoodononesideoftheGreatDivideandIontheother. TheFather﹣DaughterDuelshiftedintohighgear档位whenyoutaughtmetodrivetheoldDodgeandIdecidedIwoulddrivethe'54Chevywhetheryoulikeditornot.ThepoliceofficerwhosentmehomeafteryoureportedtheChevystolendidn'thavemuchtoleranceforastubborn16﹣year﹣oldwhileyouweresotolerantaboutitDadandIthinkthatwasprobablywhatmadeittheworstnightofmylife. OurrelationshipgreatlyimprovedwhenImarriedamanyoulikedandthingsreallyturnedaroundwhenwebeganmakingbabiesrightandleft.Somewherealongthelinethegenerationgapdisappeared.IsupposeIsawusandourrelationshipasagingtogetherratherlikeafinewine. Butthestrangestthinghappenedlastweek.IwasatastopsignandIwatchedasyouturnedthecornerinyourcar.Itdidn'timmediatelyoccurtomethatitwasyoubecausethemandrivinglookedsoelderlyandfragilebehindthewheelofthathugecar.Itwasratherlikeaslapinthefacedeliveredfromoutofnowhere.PerhapsIsawyourageforthefirsttimethatday. IguesswhatI'mtryingtosayDadiswhateverysonanddaughterwantstosaytotheirDadtoday.HonoringafatheronFather'sDayisaboutrespectandsharingandacceptanceandtoleranceandgivingandtaking.It'saboutlovingsomeonemorethanwordscansayandit'swishingthatitneverhadtoend. IloveyouDad. Love Jenny 1HowdidJennyprobablyfeelonthenightshewassenthomebythepolice A.Disappointed. B.Nervous. C.Guilty. D.Frightened. 2WecanlearnfromthepassagethatJennyandherfather. A.keptintouchbywritingeachother B.areseparatedduetothegenerationgap C.havebeengettingalongverywell D.hadahardtimeunderstandingeachother 3WhydidJennyfeelstrangewhenshesawherfatherlastweek A.Sheseldomsawhimdrivingthathugecar. B.Shehadneverrealizedhisbeingoldandweak. C.Shedidn'texpecttomeetwithhimthere. D.Shehadneverseenhimdrivingsoslowlybefore. 4Jennywrotehisfatherthisletterto. A.tellhimabouttheirconflicts B.saysorryforherbeingstubborn C.expresshergratitudetohim D.remindhimoftheearlyincident
Tosomeonestuckinatrafficjamtheabilitytoflyrightoverothercarsseemslikeadream.1Thatmaybechanging.Nearlyadozencompaniesaroundtheglobearecompetingtobethefirsttodevelopaflyingcar. Oneoftheideasbeingdevelopedisacarwithwingsthatunfoldforflight.Butmostaren'tcarsatall.Theyaremorelikehelicoptersandareoperatedbyabattery﹣poweredmotor.2Companieshavetoconvincethegovernmentthattheflyingcarsaresafe.Theywillalsoneedlonger﹣lastingbatteries.Andcitieswillhavetofigureouthowtohandlethousandsofflyingcarsinthesky. Stillsomecompaniesaremovingforward.3Especiallyascitiesgrowmorecrowdedandpeoplespendmoretimebeingstuckintraffic.Thesetaxiswoulddeliverpassengerstotherooftopsofofficebuildingsduringrushhours. Inaslittleas10yearsproductscouldbeonthemarketthatrevolutionizeurbantravelformillionsofpeoplesaidZackLovering.Heistheleaderofaprojecttodevelopaself﹣flyingtaxiforAirbusaEuropeancompanythatmakesairplanes.4Uberdoesn'thaveanyplanstodevelopaflyingcaritself.Butthecompanyisadvisingseveralcompaniesthataredevelopingthem. 5Designersthinkthatifenoughpeoplewanttobuythempricescanbekeptaffordable. A.Someflyingcarsaredesignedforhumanpilots. B.It'sstillunclearhowmuchflyingcarswillcost. C.Theyseeaneedforairtaxisandpersonallyownedflyingcars. D.Companieswillalsohavetogetpermissionfromthegovernment. E.TheUberride﹣sharecompanyseesairtaxisasthefutureofon﹣calltransportation. F.Inventorsandbusinesspeopletriedtomakeflyingcarsbuthaveneverbeenableto. G.Therearemanychallengesthatcouldkeepflyingcarsfrombecomingpartofeverydaylife.
A XICHANGMarch10Xinhua﹣WithaLongMarch﹣3BrocketputtinganewcommunicationsatelliteintoorbitonSundayChina'sLongMarchcarrierrocketseriescompleted300launches1sendmorethan500spacecraftintospacesince1970. Ittook37yearsfortheLongMarchrocketstocompletethefirst100launches7.5yearstocompletethe2two100launchesandonlyaboutfouryearstoaccomplishthefinal1003theaveragenumberoflaunchesperyearincreasingfrom2.7to13.3andthento23.5. IntensivelauncheshavebecomenormalinChinaindicatingtherapid4developofthespaceindustrytheprogressofscienceandtechnologyandtheenhancementofnationalstrengthsaidShangZhidirectoroftheSpaceDepartmentoftheCASC. B TheInternationalHorticulturalExhibition世园会2019BeijingChinaistheworldfirst﹣classhorticulturalexporecognizedbytheInternationalExhibitionsBureauhostedbytheChinesegovernmentandundertakenbytheBeijingMunicipality.It'llbeheldfromApril29thtoOctober7thinYanqingDistrictBeijingthisyear.Atpresentthe5preparefortheBeijingExpo2019haveenteredthefinaldecisivestage6itisexpectedtobecomeaninternationalhorticulturalexpowiththelargestexhibitionscalethemostexhibitorsandthe7wideinfluence. C Thefirst﹣everimageofablackholeajointeffortofmorethan200astronomersworldwide8include16fromtheChinesemainlandwasreleased9April10. Ittookaninternationalscientificteamtocapturetheimage10wasannouncedthroughcoordinatednewsconferencesaroundtheworld.
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