2009 年四川省南充市中考数学真题及答案
(满分 100 分,考试时间 90 分钟)
一、细心选一选(本大题共 8 个小题,每小题 3 分,共 24 分)每小题下面都有代号为 A、B、C、D的四个
选项,其中只有一个选项是正确的,请把正确选项的代号填在该题后面的括号内.填写正确记 3 分,不填、
填错或填出的代号超过一个均记 0 分.
1.计算
2009
( 1)
的结果是(
)
B.1
A. 1
2.在平面直角坐标系中,点 (2 5)
C. 2009
D. 2009
A , 与点 B关于 y 轴对称,则点 B的坐标是(
)
A.( 5
,
2)
B.( 2
,
5)
C.( 2 5)
,
D.(2
5),
3.某物体的展开图如图 1,它的左视图为(
)
图 1
3)(
x
4.方程(
x
A.
1)
的解是(
3
x
B.
)
C.
D.
x
B. 3
x 或 0
A. 0
5.已知一组数据 2,1, x ,7,3,5,3,2 的众数是 2,则这组数据的中位数是(
A.2
C. 3
D. 3
x 或
x
B.2.5
x
x
D.5
C.3
1
)
6.化简 1 2
)x
(
3
x
的结果是(
)
A. 5x
B. 4x
C. x
D.
1
x
7.抛物线
y
(
a x
1)(
x
3)(
a
的对称轴是直线(
0)
)
D
O
A
B
1
C.
B.
x
x
A. 1x
8.如图 2,AB是 O⊙ 的直径,点 C、D在 O⊙ 上,
AD OC∥ ,则 AOD
A.70°
二、认真填一填(本大题共 4 个小题,每小题 3 分,共 12 分)请将答案直接填写在题中横线上.
D. 3
x
BOC
)
C.50°
C
(图 2)
°,
B.60°
D.40°
110
(
3
9.不等式5(
x
1) 3
x
1
的解集是
.
10.某校为了举办“庆祝建国 60 周年”的活动,调查了本校所有学生,调查的结果如图 3 所示,根据图中
给出的信息,这所学校赞成举办演讲比赛的学生有
人.
A
40%
C
B
35%
人数
160
A:文化演出
B:运动会
C:演讲比赛
0
(图 3)
A
B
C
活动形式
B
°,
BC
7
AD
4
,
.
AB
11.如图 4,等腰梯形 ABCD中, AD BC∥ ,
60
,则梯形 ABCD
的周长是
6cm
12. ABC△
以点 B为圆心、6cm 为半径作 B⊙ ,则边 AC所在的直线
与 B⊙ 的位置关系是
三、(本大题共 2 个小题,每小题 6 分,共 12 分)
10cm
8cm
BC
,
AC
中,
.
,
A
D
,
B
C
(图 4)
13.计算:
(π 2009)
0
12 | 3 2 |
.
14.化简:
x
x
1
2
2
x
1
2
x
2
x
4
1
1
x
.
四、(本大题共 2 个小题,每小题 6 分,共 12 分)
15.如图 5,ABCD是正方形,点 G是 BC上的任意一点, DE
求证: AF BF EF
.
AG⊥ 于 E, BF DE∥ ,交 AG于 F.
A
D
E
B
F
G
C
16.甲口袋中装有两个相同的小球,它们分别写有 1 和 2;乙口袋中装有三个相同的小球,它们分别写有 3、
4 和 5;丙口袋中装有两个相同的小球,它们分别写有 6 和 7.从这 3 个口袋中各随机地取出 1 个小球.
(1)取出的 3 个小球上恰好有两个偶数的概率是多少?
(2)取出的 3 个小球上全是奇数的概率是多少?
(图 5)
五、(本大题共 2 个小题,每小题 8 分,共 16 分)
17.在达成铁路复线工程中,某路段需要铺轨.先由甲工程队独做 2 天后,再由乙工程队独做 3 天刚好完
成这项任务.已知乙工程队单独完成这项任务比甲工程队单独完成这项任务多用 2 天,求甲、乙工程队单
独完成这项任务各需要多少天?
18.如图 6,在平面直角坐标系中,已知点 (4 2)
B , , BA
x⊥ 轴于 A.
的值;
(1)求 tan BOA
(2)将点 B绕原点逆时针方向旋转 90°后记作点C ,求点C 的坐标;
(3)将 OAB△
作出 O A B
平移得到 O A B
,并写出点O 、 A 的坐标.
△
△
y
,点 A的对应点是 A ,点 B 的对应点 B 的坐标为 (2
2), ,在坐标系中
B
1
O
1
A
x
(图 6)
六、(本大题 8 分)
19.某电信公司给顾客提供了两种手机上网计费方式:
方式 A以每分钟 0.1 元的价格按上网时间计费;方式 B除收月基费 20 元外,再以每分钟 0.06 元的价格按
上网时间计费.假设顾客甲一个月手机上网的时间共有 x 分钟,上网费用为 y 元.
(1)分别写出顾客甲按 A、B两种方式计费的上网费 y 元与上网时间 x 分钟之间的函数关系式,并在图 7
的坐标系中作出这两个函数的图象;
(2)如何选择计费方式能使甲上网费更合算?
y/元
10
O
100
(图 7)
x/分
BC .
6
七、(本大题 8 分)
20.如图 8,半圆的直径
(1)求弦 AC 的长;
(2)若 P为 AB的中点, PE
AB ,点 C在半圆上,
10
AB⊥ 交 AC 于点 E,求 PE 的长.
C
E
A
P
(图 8)
B
八、(本大题 8 分)
21.如图 9,已知正比例函数和反比例函数的图象都经过点 (3 3)
A , .
(1)求正比例函数和反比例函数的解析式;
(2)把直线 OA向下平移后与反比例函数的图象交于点 (6
(3)第(2)问中的一次函数的图象与 x 轴、 y 轴分别交于 C、D,求过 A、B、D三点的二次函数的解析式;
(4)在第(3)问的条件下,二次函数的图象上是否存在点 E,使四边形 OECD的面积 1S 与四边形 OABD的
m, ,求 m 的值和这个一次函数的解析式;
B
)
S
面积 S 满足: 1
S
2
3
?若存在,求点 E的坐标;若不存在,请说明理由.
A
B
3
C
6
x
y
3
O
D
南充市二○○九年高中阶段学校招生统一考试
数学试卷参考答案及评分意见
说明:
1. 全卷满分 100 分,参考答案和评分意见所给分数表示考生正确完成当前步骤时应得的累加分数.
2. 参考答案和评分意见仅是解答的一种,如果考生的解答与参考答案不同,只要正确就应该参照评分意见
给分.合理精简解答步骤,其简化部分不影响评分.
3. 要坚持每题评阅到底.如果考生解答过程发生错误,只要不降低后继部分的难度且后继部分再无新的错
误,可得不超过后继部分应得分数的一半,如果发生第二次错误,后面部分不予得分;若是相对独立的
得分点,其中一处错误不影响其它得分点的评分.
2.C
4.D
一、细心选一选(本大题共 8 个小题,每小题 3 分,共 24 分)
1.A
二、认真填一填(本大题共 4 个小题,每小题 3 分,共 12 分)
9. 3x
三、(本大题共 2 个小题,每小题 6 分,共 12 分)
12.相切
10.100
11.17
3.B
5.B
6.C
7.A
8.D
13.解:原式 1 2 3 2
3
·········································· [共 4 分,分项给分:
(π 2009)
0
(1 分), 12
1
2 3
(1 分),| 3 2 | 2
(2 分)]
3
(1 2)
(2 3
3)
(结果正确,没有此步不扣分)
. ·········································································(6 分)
3
3
x
x
1
2
2
x
4
2
x
1
1
1
x
2
x
······················································· (1 分)
x
x
x
x
x
x
x
x
x
1
2)
2
1
2)(
x
(
1)
x
1
··················································· (3 分)
······································································· (4 分)
1 (
2
2
1
x
2 1
1
x
1
················································································· (5 分)
1
1
1 ·······················································································(6 分)
14.解:原式
°.····································································· (1 分)
90
BAD
四、(本大题共 2 个小题,每小题 6 分,共 12 分)
15.证明: ABCD 是正方形,
AD AB
,
DE
AG
⊥ ,
又
BF DE
∥ ,
90
°.
90
°.
DEG
ADE
ADE
AED
DAE
BAD
DAE
BAF
BAF
°,
90
DEG
AFB
.················································································ (2 分)
在 ABF△
与 DAE△
中,
AED
.····································································(3 分)
AFB
ADE
AD AB
AED
BAF
,
△
ABF
≌△
DAE
(AAS)
.······································································(4 分)
BF AE
AF AE EF
AF BF EF
16.解:根据题意,画出如下的“树形图”:
.·························································································· (5 分)
.·················································································· (6 分)
,
甲
乙
丙
1
4
3
5
3
2
4
5
6
7
6
7
6
7
6
7
6
7
6
7
从树形图看出,所有可能出现的结果共有 12 个.············································ (2 分)
(1)取出的 3 个小球上恰好有两个偶数的结果有 4 个,即 1,4,6;2,3,6;2,4,7;2,5,6.所以
P (两个偶数)
4
12
.········································································ (4 分)
1
3
(2)取出的 3 个小球上全是奇数的结果有 2 个,即 1,3,7;1,5,7.所以
P (三个奇数)
2
12
.········································································ (6 分)
1
6
五、(本大题共 2 个小题,每小题 8 分,共 16 分)
17.解:设甲工程队单独完成任务需 x 天,则乙工程队单独完成任务需 (
x 天,
2)
······················································(1 分)
.············································································ (4 分)
1
2
依题意得
3
x
化为整式方程得
2
x
x
2 3
x
························································································· (5 分)
x .················································································(6 分)
x 或 4
解得
检验:当 4
x 时, (
x x
1
2)
,
0
4 0
1
x 和
1
4
1
x 不符合实际意义,故
x 都是原分式方程的解.
x 舍去;···················································(7 分)
x 和
1
但
乙单独完成任务需要 2 6
答:甲、乙工程队单独完成任务分别需要 4 天、6 天.······································(8 分)
18.解:(1)点 (4 2)
x (天).
x⊥ 轴于 A ,
B , , BA
,
y
C D
OA
tan
4
,
BOA
BA
2
AB
OA
2
4
(2)如图,由旋转可知:
1
2
CD BA
点C 的坐标是 ( 2 4)
(3) O A B
O , , (2
A
( 2
4)
△
如图所示,
.························· (3 分)
2
,
OD OA
4
,
, .······························· (5 分)
B
x
1
O
1
A
B
A
O
, .······························ (8 分)
4)
六、(本大题 8 分)
19.(1)方式 A: 0.1 (
x x
y
≥ ,·····························································(1 分)
0)
方式 B: 0.06
y
x
20(
x
≥ ,································································ (2 分)
0)
两个函数的图象如图所示.········································································· (4 分)
y/元
方式 A
P
方式 B
100
500
x/分
50
20
10
O
(2)解方程组
y
y
0.1
x
0.06
x
20
得
x
y
500
50
所以两图象交于点 P(500,50).································································· (5 分)
由图象可知:当一个月内上网时间少于 500 分时,选择方式 A省钱;当一个月内上网时间等于 500 分时,
选择方式 A、方式 B一样;当一个月内上网时间多于 500 分时,选择方式 B省钱.· (8 分)
七、(本大题 8 分)
20.解: AB 是半圆的直径,点C 在半圆上,
°.
ACB
90
2
2
8
2
6
90
2
10
°,
AB
BC
··································· (3 分)
在 Rt ABC△
AC
中,
AB
(2) PE
⊥ ,
90
APE
ACB
°.
APE
ACB
.
CAB
又 PAE
ABC
AEP
△
∽△
PE
AP
····························································································(7 分)
BC AC
10
8
.···················································································· (8 分)
,
,··············································································· (6 分)
PE
6
1
2
PE
30
8
15
4
八、(本大题 8 分)
21.解:(1)设正比例函数的解析式为
y
1(
k x k
1
,
0)
因为
y
k x 的图象过点 (3 3)
A , ,所以
1
1
k .
3 3k ,解得 1 1
这个正比例函数的解析式为 y
设反比例函数的解析式为
x .······························································ (1 分)
k
2
x
的图象过点 (3 3)
A , ,所以
.
2(
k
0)
y
因为
y
2k
x
k ,解得 2
3
k .
9
2
3
这个反比例函数的解析式为
y
.····························································· (2 分)
9
x
(2)因为点 (6
B
m, 在
)
y
的图象上,所以
9
x
m ,则点
9
6
3
2
B
36
, .······································································ (3 分)
2
设一次函数解析式为
y
3(
k x b k
3
.
0)
因为
y
k x b
3
的图象是由 y
x 平移得到的,
所以 3 1
k ,即 y
.
x b
又因为 y
的图象过点
x b
B
36
, ,所以
2
b
6
,解得
3
2
一次函数的解析式为
9
2
y
b ,
x .·······························································(4 分)
9
2
(3)因为
y
x 的图象交 y 轴于点 D ,所以 D 的坐标为
9
2
9
0
, .
2
设二次函数的解析式为
y
2
ax
bx
(
c a
.
0)
因为
y
2
ax
bx
的图象过点 (3 3)
A , 、
c
B
36
, 、和 D
2
9
0
, ,
2
所以
,·················(5 分)
a
3
b c
9
36
6
a
b c
9 .
c
2
3
,
3
2
解得
,
1
a
2
4
b
,
9 .
c
2
这个二次函数的解析式为
y
21
x
2
4
x
.·············································· (6 分)
9
2
(4)
y
x
交 x 轴于点C ,点C 的坐标是
9 0
, ,
2
如图所示,
3 3
6 6
6
3
1
2
1 3
2 2
1
2
9
2
15
2
9
2
S
9
4
45 18
81
4
.
A
E
3
B
6
C
x
y
3
O
D