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如图,在菱形ABCD中,点E是AD的中点,对角线AC、BD交于点F,若菱形ABCD的周长是24,则EF= .
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求证菱形的两条对角线互相垂直.已知如图四边形ABCD是菱形对角线ACBD交于点O..求证AC⊥BD.
③→②→①→④
③→④→①→②
①→②→④→③
①→④→③→②
如图在菱形ABCD中对角线AC.BD相交于点O.E.为AB的中点且OE=a则菱形ABCD的周长为
16a
12a
8a
4a
如图菱形ABCD的对角线ACBD相交于点O.E.为AD的中点若OE=3则菱形ABCD的周长为
如图菱形ABCD中对角线ACBD相交于点O.H.为AD边中点菱形ABCD的周长为24则OH的长等于.
如图在▱ABCD中对角线AC与BD交于点O.若增加一个条件使▱ABCD成为菱形下列给出的条件不正确的
AB=AD
AC⊥BD
AC=BD
∠BAC=∠DAC
如图菱形中对角线AC.BD交于点O.E.为AD边中点菱形ABCD的周长为28则OE的长等于
3.5
4
7
14
如图在菱形ABCD中对角线AC.BD相交于点O且AC=12BD=16E为AD的中点点P在BD上移动若
如图菱形ABCD中对角线AC.BD相交于点OH为AD边中点菱形ABCD的周长为28则OH的长等于
3.5
4
7
14
如图菱形ABCD中对角线ACBD相关于点O.且AC=16BD=12E.为AD的中点点P.在x轴正半轴
如图菱形ABCD中对角线ACBD相交于点O.H.为AD边中点菱形ABCD的周长为24则OH的长等于.
如图在菱形ABCD中AD=6∠ABC=120°E.是BC的中点P.为对角线AC上的一个动点则PE+P
如图在菱形ABCD中对角线AC.BD相交于点O.E.为BC的中点则下列式子中一定成立的是
AC=2OE
BC=2OE
AD=OE
OB=OE
如图所示菱形ABCD中对角线AC.BD相交于点O.H.为AD边的中点菱形ABCD的周长为28则OH的
3.5
4
7
14
如图在菱形ABCD中对角线ACBD相交于点O.E.为BC的中点若菱形的周长为80则OE=______
图菱形ABCD中对角线AC.BD相交于点O.H.为AD边中点菱形ABCD的周长为28则OH的长等于
3.5
4
7
14
如图所示菱形ABCD中对角线ACBD相交于点O.H.为AD边中点OH的长为3则菱形ABCD的周长等于
如图在菱形ABCD中对角线AC.BD相交于点O.E.为BC的中点则下列式子中一定成立的是
AC=2OE
BC=2OE
AD=OE
OB=OE
如图在菱形ABCD中对角线ACBD相交于点O.H.为AD边中点菱形ABCD的周长为24则OH的长等于
如图在菱形ABCD中对角线ACBD相交于点O.H.为AD边中点菱形ABCD的周长为28则OH的长等于
如图所示菱形ABCD中对角线ACBD相交于点OH为AD边中点菱形ABCD的周长为24则OH的长等于.
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Istillremembermymiddleschoollifeinthatsmalltown.IamtheninaschoolforstudentsfromTibet.Aswealllefthomeataearlyagewemetlotsofproblemsinourdailylife.Wehadtodothewashingcleaningandshoppingbyus.Howeverweseldomfeltlonelyorhelplessly.Weenjoyedourhappylife.Atweekendswewouldplaybasketballswaminthepoolorgoforapicnic.Wearelivedinabigfamily.Wetreatedeachotherbrothersandsisters.Ifanyoneofushadanydifficultywithhisstudiestheotherstudentwouldhelphimout.Ithasbeenfiveyearswhenwegraduatedbutthosememoriesareassweetasneverbefore.
小美从某粒子结构示意图如图中获取了下列信息其中错误的是
Mygrandmotherwasalwaysencouragingmetosetgoalsandworkhardtoachievethem.Shewouldtellmenottobeafollowerandnottoset1onwhatIcouldachieve.She2believedthattherewerenolimitsthatyoucould3whateveryouwanted.Iwouldneverforgetthefollowingstorythatsheoncetoldme.Afarmerwonfirst4atthecountryfairforhishugeradish小萝卜thatwastheexactshapeand5ofamilkbottle.Manywere6astohowthefarmerwasabletogrowthisradishthatwastheexactshapeofamilkbottle.7onegentlemanwentuptothefarmerandaskedthequestion.Thefarmerreplied'Itwas8.IgottheseedgrowingandthenIputitintothemilkbottle.Ithad9elsetogo.'Youcanusethisstoryasananalogy比喻tolife﹣ourlivesare10bythekindofsurroundingsweplaceourselvesinthepeoplethatweallowto11usandthegoalswegiveourselves.Ifweonly12andtakenoactionthenwegetnofurther.Butifwe13setagoalandtakeactionthenourlifetakesa14shape.Goalsandactionscanhelpusaccomplishmoreinayearthanwhatsomepeoplewillaccomplishinalifetime.Toprovethis15readthebiographiesof16peopleandyouwillseethatgoalsandactions17playedabigroleintheirsuccess.Rememberthe18ofMaryKayAshwhosaid'Don'tlimityourself.Manypeoplelimitthemselvestowhattheythinktheycando.Youcango19yourmindletsyou.Whatyoubelieverememberyoucanachieve.'Insummarydon'tputyourselfinabottleinotherwordsmoveoutofwhatis20andsecureifyouwanttomoveforward.1A.expectations B.rules C.limits D.lines2A.truly B.naturally C.tightly D.partly3A.win B.grasp C.realize D.achieve4A.price B.prize C.position D.award5A.size B.length C.weight D.height6A.doubtful B.worried C.anxious D.curious7A.Immediately B.Gradually C.Finally D.Actually8A.strange B.easy C.funny D.secret9A.nowhere B.everywhere C.somewhere D.anywhere10A.shaped B.formed C.controlled D.improved11A.understand B.help C.influence D.contact12A.dream B.refuse C.doubt D.change13A.struggle B.refuse C.continue D.plan14A.beautiful B.different C.solid D.clear15A.truth B.lesson C.point D.evidence16A.successful B.brave C.friendly D.careful17A.asusual B.aboveall C.atall D.infact18A.case B.wisdom C.thought D.speech19A.asif B.incase C.asfaras D.aslongas20A.comfortable B.valuable C.ordinary D.boring
根据如图所示四个实验按要求填空. 1在实验室用A装置制取二氧化碳所用药品为指出用该装置制取二氧化碳气体的一个明显错误的是. 2B实验的试管1中产生的气体是写化学式由此实验得出水是由组成的. 3C实验中将镁条在空气中点燃后再放入充满CO2的集气瓶中发现镁条继续激烈燃烧发出白光放热产生一种白色固体和一种黑色固体已知该反应为置换反应则反应的化学方程式为. 4用D装置干燥并收集某气体该气体可能是写化学式填一种即可.
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