您好,欢迎访问三七文档
当前位置:首页 > 商业/管理/HR > 质量控制/管理 > 2009年广西河池市中考数学试卷
年河池市初中毕业暨升学统一考试数学(考试时间120分钟,满分120分)一、填空题(本大题共10小题,每小题2分,共20分,请将正确答案填写在题中的横线上.)1.如果上升3米记作+3米,那么下降2米记作米.2.如图1,已知AB∥CD,则∠A=度.3.今年我市初中毕业暨升学统一考试的考生约有35300人,该数据用科学记数法表示为人.4.投掷一枚质地均匀的正方体骰子,朝上的一面为6点的概率是.5.分解因式:24x.6.已知一组数据1,a,3,6,7,它的平均数是4,这组数据的众数是.7.如图2,ABC△的顶点坐标分别为(36)(13)AB,,,,(42)C,.若将ABC△绕C点顺时针旋转90,得到ABC△,则点A的对应点A的坐标为.8.已知关于x、y的一次函数12ymx的图象经过平面直角坐标系中的第一、三、四象限,那么m的取值范围是.9.如图3,PA,PB切⊙O于A,B两点,若60APB∠,⊙O的半径为3,则阴影部分的面积为.10.某小区有一块等腰三角形的草地,它的一边长为20m,面积为2160m,为美化小区环境,现要给这块三角形草地围上白色的低矮栅栏,则需要栅栏的长度为m.二、选择题(本大题共8小题,每小题3分,共24分;在每小题给出的四个选项中,只有一项是正确的,请将正确答案的代号填入题后的括号内,每小题选对得3分,选错、不选或多选均得零分.)11.下列运算正确的是()1234567891234567OABCyx图2APBO图3CDB图180A.623)(aaB.22aaaC.2aaaD.236aaa12.下列事件是随机事件的是()A.在一个标准大气压下,加热到100℃,水沸腾B.购买一张福利彩票,中奖C.有一名运动员奔跑的速度是30米/秒D.在一个仅装着白球和黑球的袋中摸球,摸出红球13.图4是圆台状灯罩的示意图,它的俯视图是()14.若两圆的半径分别是1cm和5cm,圆心距为6cm,则这两圆的位置关系是()A.内切B.相交C.外切D.外离15.一个不等式的解集为12x≤,那么在数轴上表示正确的是()16.已知菱形的边长和一条对角线的长均为2cm,则菱形的面积为()A.23cmB.24cmC.23cmD.223cm17.如图5,A、B是函数2yx的图象上关于原点对称的任意两点,BC∥x轴,AC∥y轴,△ABC的面积记为S,则()A.2SB.4SC.24SD.4S18.如图6,在Rt△ABC中,90A,AB=AC=86,点E为AC的中点,点F在底边BC上,且FEBE,则△CEF的面积是()A.16B.18C.66D.76三、解答题(本大题共8小题,满分76分,解答应写出文字说明、证明过程或演算步骤.)19.(本小题满分9分)计算:0234sin30251102ABCD102102102OBxyCA图5CBFAE图6A.B.C.D.图4·.(本小题满分9分)如图7,在△ABC中,∠ACB=2B.(1)根据要求作图:①作ACB的平分线交AB于D;②过D点作DE⊥BC,垂足为E.(2)在(1)的基础上写出一对全等三角形和一对相似比不为.......1.的相似三角形:△≌△;△∽△.请选择其中一对加以证明.21.(本小题满分8分)如图8,为测量某塔AB的高度,在离该塔底部20米处目测其顶A,仰角为60,目高1.5米,试求该塔的高度(31.7)≈.ACB图71.5图8DBC60A1.5.(本小题满分8分)某校为了解九年级学生体育测试情况,以九年级(1)班学生的体育测试成绩为样本,按ABCD,,,四个等级进行统计,并将统计结果绘制成如下的统计图,请你结合图中所给信息解答下列问题:(说明:A级:90分~100分;B级:75分~89分;C级:60分~74分;D级:60分以下)(1)请把条形统计图补充完整;(2)样本中D级的学生人数占全班学生人数的百分比是;(3)扇形统计图中A级所在的扇形的圆心角度数是;(4)若该校九年级有500名学生,请你用此样本估计体育测试中A级和B级的学生人数约为人.23.(本小题满分10分)铭润超市用5000元购进一批新品种的苹果进行试销,由于销售状况良好,超市又调拨11000元资金购进该品种苹果,但这次的进货价比试销时每千克多了0.5元,购进苹果数量是试销时的2倍.(1)试销时该品种苹果的进货价是每千克多少元?(2)如果超市将该品种苹果按每千克7元的定价出售,当大部分苹果售出后,余下的400千克按定价的七折(“七折”即定价的70﹪)售完,那么超市在这两次苹果销售中共盈利多少元?B46%C24%DA20%等级人数DCBA12231015253020105.(本小题满分10分)为了预防流感,某学校在休息天用药熏消毒法对教室进行消毒.已知药物释放过程中,室内每立方米空气中的含药量y(毫克)与时间x(分钟)成正比例;药物释放完毕后,y与x成反比例,如图9所示.根据图中提供的信息,解答下列问题:(1)写出从药物释放开始,y与x之间的两个函数关系式及相应的自变量取值范围;(2)据测定,当空气中每立方米的含药量降低到0.45毫克以下时,学生方可进入教室,那么从药物释放开始,至少需要经过多少小时后,学生才能进入教室?25.(本小题满分10分)如图10,在⊙O中,AB为⊙O的直径,AC是弦,4OC,60OAC.(1)求∠AOC的度数;(2)在图10中,P为直径BA延长线上的一点,当CP与⊙O相切时,求PO的长;(3)如图11,一动点M从A点出发,在⊙O上按逆时针方向运动,当MAOCAOSS△△时,求动点M所经过的弧长.O9(毫克)12(分钟)xy图9·图11MOBACACOPB图10.(本小题满分12分)如图12,已知抛物线243yxx交x轴于A、B两点,交y轴于点C,抛物线的对称轴交x轴于点E,点B的坐标为(1,0).(1)求抛物线的对称轴及点A的坐标;(2)在平面直角坐标系xoy中是否存在点P,与A、B、C三点构成一个平行四边形?若存在,请写出点P的坐标;若不存在,请说明理由;(3)连结CA与抛物线的对称轴交于点D,在抛物线上是否存在点M,使得直线CM把四边形DEOC分成面积相等的两部分?若存在,请求出直线CM的解析式;若不存在,请说明理由.ODBCAxyE图12年河池市初中毕业暨升学统一考试数学科评分标准一、填空题:1.-22.1003.43.53104.165.(2)(2)xx6.37.(8,3)8.1m9.933π10.20489或4085或40165二、选择题:11.A12.B13.D14.C15.A16.D17.B18.A三、解答题:19.解:原式134412···································································(8分)32412··································································(9分)20.解:(1)①正确作出角平分线CD;············(2分)②正确作出DE.··························(4分)(2)△BDE≌△CDE;························(5分)△ADC∽△ACB.·························(6分)选择△BDE≌△CDE进行证明:∵DC平分∠ACB∴∠DCE12∠ACB又∵∠ACB2∠B∴∠B12∠ACB∴∠DCE∠B······································································(7分)∵DE⊥BC∴∠DEC∠DEB90°·····································(8分)又∵DEDE∴△BDE≌△CDE(AAS)································(9分)或选择△ADC∽△ACB进行证明:∵DC平分∠ACB∴∠ACD12∠ACB又∵∠ACB2∠B∴∠B12∠ACB········································(7分)∴∠ACD∠B········································································(8分)又∵∠A∠A∴△ADC∽△ACB·······································(9分)21.解:如图,CD20,∠ACD60°,·······················································(2分)在Rt△ACD中,tanACDADCD························································(5分)∴320AD······················································································(6分)∴AD203≈34················································································(7分)ACEBD又∵BD1.5∴塔高AB341.535.5(米)····(8分)22.(1)条形图补充正确;··················(2分)(2)10﹪;··································(4分)(3)72°;···································(6分)(4)330.···································(8分)23.解:(1)设试销时这种苹果的进货价是每千克x元,依题意,得·····················(1分)11000500020.5xx····································································(5分)解之,得x5········································································(6分)经检验,x5是原方程的解.······················································(7分)(2)试销时进苹果的数量为:500010005(千克)第二次进苹果的数量为:2×10002000(千克)····································(8分)盈利为:2600×7+400×7×0.7-5000-110004160(元)····················(9分)答:试销时苹果的进货价是每千克5元,商场在两次苹果销售中共盈利4160元.····································
本文标题:2009年广西河池市中考数学试卷
链接地址:https://www.777doc.com/doc-3091192 .html