2007年长沙市初中毕业学业考试试卷
数 学
考生注意:本试卷共26道小题,时量120分钟,满分120分. 一、填空题(本题共8个小题,每小题3分,满分24分)
1.如图,已知直线a ∥b ,∠1=35,则∠
2
2.请写出一对互为相反数的数:
a
b
x y
3.计算-=.
x -y x -y
4.△ABC 中,D ,E 分别是AB ,AC 的中点,当BC =10cm 时,DE =cm . 5.投掷一枚质地均匀的普通骰子,朝上的一面为6点的概率是. 6=.
7.单独使用正三角形、正方形、正六边形、正八边形四种地砖,不能镶嵌(密铺)地面的是 .
8.如图,点A ,B 在数轴上对应的实数分别为m (用,n ,则A ,B 间的距离是.含m ,n 的式子表示)
二、选择题(本题共8个小题,每小题3分,满分24分) 请将你认为正确的选择支的代号填在下面的表格里: -4) 所在的象限是( ) 9.在平面直角坐标系中,点(3,
A .第一象限 B .第二象限 C .第三象限 D .第四象限
10.下列说法正确的是( )
A .有两个角为直角的四边形是矩形 B .矩形的对角线互相垂直 C .等腰梯形的对角线相等 D .对角线互相垂直的四边形是菱形 则卖报数的众数是( ) A .25 B .26 C .27 D .28
12.经过任意三点中的两点共可以画出的直线条数是( ) A .一条或三条 B .三条 C .两条 D .一条
13.星期天,小王去朋友家借书,下图是他离家的距离y (千米)与时间x (分钟)的函数
图象,根据图象信息,下列说法正确的是( )A .小王去时的速度大于回家的速度
B .小王在朋友家停留了10分钟
C .小王去时所花的时间少于回家所花的时间
D .小王去时走上坡路,回家时走下坡路
14.把抛物线y =-2x 2向上平移1个单位,得到的抛物线是( ) A .y =-2(x +1) 2 C .y =-2x 2+1
B .y =-2(x -1) 2
D .y =-2x 2-1
15
.圆锥侧面展开图可能是下列图中的(
)
A . B . C . D .
16.在密码学中,直接可以看到内容为明码,对明码进行某种处理后得到的内容为密码.有一种密码,将英文26个字母a ,b ,c ,„,z (不论大小写)依次对应1,2,3,„,26这26个自然数(见表格).当明码对应的序号x 为奇数时,密码对应的序号y =当明码对应的序号x 为偶数时,密码对应的序号y =x +1
;2
x
+13. 按上述规定,将明码“love ”译成密码是( ) A .gawq B .shxc C .sdri D .love
三、解答题(本题共6个小题,每小题6分,满分36分) 17.计算:(-3) --
18.解分式方程:
2
1
+2-1. 2
23=. x -3x
19.如图是某设计师在方格纸中设计图案的一部分,请你帮他完成余下的工作: (1)作出关于直线AB 的轴对称图形;
(2)将你画出的部分连同原图形绕点O 逆时针旋转90;
(3)发挥你的想象,给得到的图案适当涂上阴影,让图案变得更加美丽. A
B
20.为了改进银行的服务质量,随机抽查了30名顾客在窗口办理业务所用的时间(单位:分钟).下图是这次调查得到的统计图.请你根据图中的信息回答下列问题: (1)办理业务所用的时间为11分钟的人数是 ; (2)补全条形统计图;
(3)这30名顾客办理业务所用时间的平均数是 分钟.
时间
21.先化简,再求值:2a (a +b ) -(a +
b ) 2,其中a =
b =
22.如图所示,某超市在一楼至二楼之间安装有电梯,天花板与地面平行,请你根据图中数据计算回答:小敏身高1.78米,她乘电梯会有碰头危险吗?姚明身高2.29米,他乘电梯会有碰头危险吗? (可能用到的参考数值:sin 27=0.45,cos 27=0.89,tan 27=0.51)
4m 二楼 A C
4m
4m
27° 一楼 B
四、解答题(本题共2个小题,每小题8分,满分16分) 23.(本题满分8分)
小华准备将平时的零用钱节约一些储存起来,他已存有62元,从现在起每个月存12元;小华的同学小丽以前没有存过零用钱,听到小华在存零用钱,表示从现在起每个月存20元,争取超过小华.
(1)试写出小华的存款总数y 1与从现在开始的月数x 之间的函数关系式以及小丽存款数y 2与月数x 之间的函数关系式;
(2)从第几个月开始小丽的存款数可以超过小华?
如图,Rt △ABC 中,∠C =90,O 为直角边BC 上一点,以O 为圆心,OC 为半径的圆恰好与斜边AB 相切于点D ,与BC 交于另一点E .
(1)求证:△AOC ≌△AOD ;
(2)若BE =1,BD =3,求 O 的半径及图中阴影部分的面积S .
A
五、解答题(本题共2个小题,每小题10分,满分20分) 25.(本题满分10分)
某班到毕业时共结余经费1800元,班委会决定拿出不少于270元但不超过300元的资金为老师购买纪念品,其余资金用于在毕业晚会上给50位同学每人购买一件文化衫或一本相册作为纪念品.已知每件文化衫比每本相册贵9元,用200元恰好可以买到2件文化衫和5本相册.
(1)求每件文化衫和每本相册的价格分别为多少元?
(2)有几购买文化衫和相册的方案?哪种方案用于购买老师纪念品的资金更充足?
如图,
ABCD 中,AB =4,BC =3,∠BAD =120,E 为BC 上一动点(不与B
重合),作EF ⊥AB 于F ,FE ,DC 的延长线交于点G ,设BE =x ,△DEF 的面积为S .
(1)求证:△BEF ∽△CEG ;
A D (2)求用x 表示S 的函数表达式,并写出x 的取值范围;
运动到何处时,S 有最大值,最大值为多少? B E
(3)当E
2007年长沙市初中毕业学业考试试卷
数学参考答案及评分标准
一、填空题 1.35 5.
2.1,-1(答案不唯一) 6
7.正八边形
3.1
4.5
1 6
8.n -m
三、解答题 17.原式=9-
11+ ······················································································ 3分 22
=9 ································································································· 6分 18.去分母,得2x =3(x -3) ··········································································· 2分 去括号,移项,合并,得x =9 ··································································· 5分
检验,得x =9是原方程的根. ··································································· 6分 19.图略.三步各计2分,共6分. 20.(1)5; ·································································································· 2分 (2)图略; ······························································································ 4分 (3)10. ································································································· 6分 21.原式=2a 2+2ab -(a 2+2ab +b 2) ······························································ 2分 =2a +2ab -a -2ab -b ································································· 3分 =a -b
······
···········
·····
···································································· 4分
当a =
2
22
2
2
b =
原式=2-2=2008-2007=1 ············································ 6分
22.作CD ⊥AC 交AB 于D ,则∠CAB =27, ················································ 1分
在Rt △ACD 中,CD =AC tan ∠CAB ······················································· 3分 =4⨯0.51=2.04(米) ···················································· 4分
所以小敏不会有碰头危险,姚明则会有碰头危险. ·········································· 6分 四、解答题
23.(1)y 1=62+12x ,y 2=20x ···································································· 4分 (2)由20x >62+12x 得x >7.75, ····························································· 7分
所以从第8个月开始小丽的存款数可以超过小华. ······································ 8分
24.(1) AB 切 O 于D ,∴OD ⊥AB ·························································· 1分 在Rt △AOC 和Rt △AOD 中,⎨
⎧OC =OD ,
··················································· 3分
⎩AO =AO
∴Rt △AOC ≌Rt △AOD (HL) ···································································· 4分
(2)设半径为r ,在Rt △ODB 中,r 2+32=(r +1) 2,解得r =4 ·························· 6分
由(1)有AC =AD ,∴AC 2+92=(AC +3) 2,解得AC =12························ 7分
∴S =
1111
AC BC -πr 2=⨯12⨯9-π⨯42=54-8π. ······························ 8分 2222
五、解答题
25.(1)设文化衫和相册的价格分别为x 元和y 元,则 ·········································· 1分
⎧x -y =9
······················································································· 3分 ⎨
⎩2x +5y =200
解得⎨
⎧x =35
y =26⎩
答:文化衫和相册的价格分别为35元和26元. ············································· 5分 (2)设购买文化衫t 件,则购买相册(50-t ) 本,则
1500≤35t +26(50-t ) ≤1530 ································································· 7分 200230≤t ≤ 99
···································· 8分 t 为正整数,∴t =23,24,25,即有三种方案. ·
解得
第一种方案:购文化衫23件,相册27本,此时余下资金293元;
第二种方案:购文化衫24件,相册26本,此时余下资金284元; 第三种方案:购文化衫25件,相册25本,此时余下资金275元; ····················· 9分 所以第一种方案用于购买教师纪念品的资金更充足. ····································· 10分 26.(1)证明略;··························································································· 3分 (2)由(1)DG 为△DEF 中EF 边上的高,
在Rt △BFE 中,∠
B =60,EF =BE sin B =
x , ·································· 4分 3-x
, 2
在Rt △CEG 中,CE =3-x ,CG =(3-x )cos 60=
∴DG =DC +CG =
11-x
,····································································· 5分
2
∴S =
12EF DG =x x , ························································ 6分 2
其中0
) a =11
2·············································· 9分
∴当x =3,即E 与C 重合时,S 有最大值. ·
····················································································· 10分 S 最大= ·
2007年长沙市初中毕业学业考试试卷
数 学
考生注意:本试卷共26道小题,时量120分钟,满分120分. 一、填空题(本题共8个小题,每小题3分,满分24分)
1.如图,已知直线a ∥b ,∠1=35,则∠
2
2.请写出一对互为相反数的数:
a
b
x y
3.计算-=.
x -y x -y
4.△ABC 中,D ,E 分别是AB ,AC 的中点,当BC =10cm 时,DE =cm . 5.投掷一枚质地均匀的普通骰子,朝上的一面为6点的概率是. 6=.
7.单独使用正三角形、正方形、正六边形、正八边形四种地砖,不能镶嵌(密铺)地面的是 .
8.如图,点A ,B 在数轴上对应的实数分别为m (用,n ,则A ,B 间的距离是.含m ,n 的式子表示)
二、选择题(本题共8个小题,每小题3分,满分24分) 请将你认为正确的选择支的代号填在下面的表格里: -4) 所在的象限是( ) 9.在平面直角坐标系中,点(3,
A .第一象限 B .第二象限 C .第三象限 D .第四象限
10.下列说法正确的是( )
A .有两个角为直角的四边形是矩形 B .矩形的对角线互相垂直 C .等腰梯形的对角线相等 D .对角线互相垂直的四边形是菱形 则卖报数的众数是( ) A .25 B .26 C .27 D .28
12.经过任意三点中的两点共可以画出的直线条数是( ) A .一条或三条 B .三条 C .两条 D .一条
13.星期天,小王去朋友家借书,下图是他离家的距离y (千米)与时间x (分钟)的函数
图象,根据图象信息,下列说法正确的是( )A .小王去时的速度大于回家的速度
B .小王在朋友家停留了10分钟
C .小王去时所花的时间少于回家所花的时间
D .小王去时走上坡路,回家时走下坡路
14.把抛物线y =-2x 2向上平移1个单位,得到的抛物线是( ) A .y =-2(x +1) 2 C .y =-2x 2+1
B .y =-2(x -1) 2
D .y =-2x 2-1
15
.圆锥侧面展开图可能是下列图中的(
)
A . B . C . D .
16.在密码学中,直接可以看到内容为明码,对明码进行某种处理后得到的内容为密码.有一种密码,将英文26个字母a ,b ,c ,„,z (不论大小写)依次对应1,2,3,„,26这26个自然数(见表格).当明码对应的序号x 为奇数时,密码对应的序号y =当明码对应的序号x 为偶数时,密码对应的序号y =x +1
;2
x
+13. 按上述规定,将明码“love ”译成密码是( ) A .gawq B .shxc C .sdri D .love
三、解答题(本题共6个小题,每小题6分,满分36分) 17.计算:(-3) --
18.解分式方程:
2
1
+2-1. 2
23=. x -3x
19.如图是某设计师在方格纸中设计图案的一部分,请你帮他完成余下的工作: (1)作出关于直线AB 的轴对称图形;
(2)将你画出的部分连同原图形绕点O 逆时针旋转90;
(3)发挥你的想象,给得到的图案适当涂上阴影,让图案变得更加美丽. A
B
20.为了改进银行的服务质量,随机抽查了30名顾客在窗口办理业务所用的时间(单位:分钟).下图是这次调查得到的统计图.请你根据图中的信息回答下列问题: (1)办理业务所用的时间为11分钟的人数是 ; (2)补全条形统计图;
(3)这30名顾客办理业务所用时间的平均数是 分钟.
时间
21.先化简,再求值:2a (a +b ) -(a +
b ) 2,其中a =
b =
22.如图所示,某超市在一楼至二楼之间安装有电梯,天花板与地面平行,请你根据图中数据计算回答:小敏身高1.78米,她乘电梯会有碰头危险吗?姚明身高2.29米,他乘电梯会有碰头危险吗? (可能用到的参考数值:sin 27=0.45,cos 27=0.89,tan 27=0.51)
4m 二楼 A C
4m
4m
27° 一楼 B
四、解答题(本题共2个小题,每小题8分,满分16分) 23.(本题满分8分)
小华准备将平时的零用钱节约一些储存起来,他已存有62元,从现在起每个月存12元;小华的同学小丽以前没有存过零用钱,听到小华在存零用钱,表示从现在起每个月存20元,争取超过小华.
(1)试写出小华的存款总数y 1与从现在开始的月数x 之间的函数关系式以及小丽存款数y 2与月数x 之间的函数关系式;
(2)从第几个月开始小丽的存款数可以超过小华?
如图,Rt △ABC 中,∠C =90,O 为直角边BC 上一点,以O 为圆心,OC 为半径的圆恰好与斜边AB 相切于点D ,与BC 交于另一点E .
(1)求证:△AOC ≌△AOD ;
(2)若BE =1,BD =3,求 O 的半径及图中阴影部分的面积S .
A
五、解答题(本题共2个小题,每小题10分,满分20分) 25.(本题满分10分)
某班到毕业时共结余经费1800元,班委会决定拿出不少于270元但不超过300元的资金为老师购买纪念品,其余资金用于在毕业晚会上给50位同学每人购买一件文化衫或一本相册作为纪念品.已知每件文化衫比每本相册贵9元,用200元恰好可以买到2件文化衫和5本相册.
(1)求每件文化衫和每本相册的价格分别为多少元?
(2)有几购买文化衫和相册的方案?哪种方案用于购买老师纪念品的资金更充足?
如图,
ABCD 中,AB =4,BC =3,∠BAD =120,E 为BC 上一动点(不与B
重合),作EF ⊥AB 于F ,FE ,DC 的延长线交于点G ,设BE =x ,△DEF 的面积为S .
(1)求证:△BEF ∽△CEG ;
A D (2)求用x 表示S 的函数表达式,并写出x 的取值范围;
运动到何处时,S 有最大值,最大值为多少? B E
(3)当E
2007年长沙市初中毕业学业考试试卷
数学参考答案及评分标准
一、填空题 1.35 5.
2.1,-1(答案不唯一) 6
7.正八边形
3.1
4.5
1 6
8.n -m
三、解答题 17.原式=9-
11+ ······················································································ 3分 22
=9 ································································································· 6分 18.去分母,得2x =3(x -3) ··········································································· 2分 去括号,移项,合并,得x =9 ··································································· 5分
检验,得x =9是原方程的根. ··································································· 6分 19.图略.三步各计2分,共6分. 20.(1)5; ·································································································· 2分 (2)图略; ······························································································ 4分 (3)10. ································································································· 6分 21.原式=2a 2+2ab -(a 2+2ab +b 2) ······························································ 2分 =2a +2ab -a -2ab -b ································································· 3分 =a -b
······
···········
·····
···································································· 4分
当a =
2
22
2
2
b =
原式=2-2=2008-2007=1 ············································ 6分
22.作CD ⊥AC 交AB 于D ,则∠CAB =27, ················································ 1分
在Rt △ACD 中,CD =AC tan ∠CAB ······················································· 3分 =4⨯0.51=2.04(米) ···················································· 4分
所以小敏不会有碰头危险,姚明则会有碰头危险. ·········································· 6分 四、解答题
23.(1)y 1=62+12x ,y 2=20x ···································································· 4分 (2)由20x >62+12x 得x >7.75, ····························································· 7分
所以从第8个月开始小丽的存款数可以超过小华. ······································ 8分
24.(1) AB 切 O 于D ,∴OD ⊥AB ·························································· 1分 在Rt △AOC 和Rt △AOD 中,⎨
⎧OC =OD ,
··················································· 3分
⎩AO =AO
∴Rt △AOC ≌Rt △AOD (HL) ···································································· 4分
(2)设半径为r ,在Rt △ODB 中,r 2+32=(r +1) 2,解得r =4 ·························· 6分
由(1)有AC =AD ,∴AC 2+92=(AC +3) 2,解得AC =12························ 7分
∴S =
1111
AC BC -πr 2=⨯12⨯9-π⨯42=54-8π. ······························ 8分 2222
五、解答题
25.(1)设文化衫和相册的价格分别为x 元和y 元,则 ·········································· 1分
⎧x -y =9
······················································································· 3分 ⎨
⎩2x +5y =200
解得⎨
⎧x =35
y =26⎩
答:文化衫和相册的价格分别为35元和26元. ············································· 5分 (2)设购买文化衫t 件,则购买相册(50-t ) 本,则
1500≤35t +26(50-t ) ≤1530 ································································· 7分 200230≤t ≤ 99
···································· 8分 t 为正整数,∴t =23,24,25,即有三种方案. ·
解得
第一种方案:购文化衫23件,相册27本,此时余下资金293元;
第二种方案:购文化衫24件,相册26本,此时余下资金284元; 第三种方案:购文化衫25件,相册25本,此时余下资金275元; ····················· 9分 所以第一种方案用于购买教师纪念品的资金更充足. ····································· 10分 26.(1)证明略;··························································································· 3分 (2)由(1)DG 为△DEF 中EF 边上的高,
在Rt △BFE 中,∠
B =60,EF =BE sin B =
x , ·································· 4分 3-x
, 2
在Rt △CEG 中,CE =3-x ,CG =(3-x )cos 60=
∴DG =DC +CG =
11-x
,····································································· 5分
2
∴S =
12EF DG =x x , ························································ 6分 2
其中0
) a =11
2·············································· 9分
∴当x =3,即E 与C 重合时,S 有最大值. ·
····················································································· 10分 S 最大= ·