a 1 a 2 ··········· ··········· ·········· ········ 分 ··········· ·········· ··········· ········ ·········· ··········· ··········· ······· 4 a 3 a 3 3 = ··········· ··········· ·········· ··········· · 6 分 ··········· ·········· ··········· ··········· · ·········· ··········· ··········· ·········· ·· a 3 ··········· ·········· ······ ·········· ··········· ····· a 取值时只要不取 2， 2 ，3 就可以． ···························7 分
EBO D 30° 又 CED BEO ， BE ED ··········· ·········· ··········· ····· ·········· ··········· ··········· ····· CDE ≌△OBE ····································· 7 分 △ 60 25π S阴 S扇OBC π 52 · (cm2 ) 360 6 25π 2 答：阴影部分的面积为 ···························· 10 ·········· ··········· ······· cm ． ····························· 分 6 22．解： （1）设 4 月初猪肉价格下调后每斤 x 元． 60 60 根据题意，得 ··········· ·········· ··········· · ·········· ··········· ··········· · 2 ··········· ··········· ·········· · 2 分 x 3x 2 解得 x 10 ·········································· 分 ··········· ·········· ··········· ·········· ·········· ··········· ··········· ········· 3 经检验， x 10 是原方程的解 ································ 分 ··········· ·········· ··········· ·········· ··········· ·········· 4
（第 21 题图）
5 3 BE 3 在 Rt△BEO 中， sin 60° = ， 2 OB 2 OB
OB 5
即 ⊙O 的半径长为 5cm ． ··························· 分 ··········· ·········· ····· 5 ·········· ··········· ····· （2）由（1）可知， O 60° BEO 90° ，
1 2 3
P(乙获胜)
0
1 0
2 1 0
3 2 1
1 2
1
由列表法可知：会产生 12 种结果，它们出现的机会相等，其中和为 1 的有 3 种结果．
3 1 ··········· ·········· ··········· ····· 6 ·········· ··········· ··········· ····· ··········· ··········· ·········· ······ 分 12 4
··········· ·········· ··········· ········ ·········· ··········· ···························· 10 分 五、解答题（每题 10 分，共 20 分） 21．解： （1） AC 与 ⊙O 相切于点 C ··········· ·········· · ·········· ··········· · ACO 90° ······················ 1 分
求值正确． ·········································· 8 分 ··········· ·········· ··········· ·········· ·········· ··········· ··········· ·········· 四、解答题（每题 10 分，共 20 分） 人数 19． 100
答：4 月初猪肉价格下调后每斤 10 元． ··························· 分 ··········· ·········· ····· 5 ·········· ··········· ····· （2）设 5、6 月份猪肉价格的月平均增长率为 y ． 根据题意，得 10(1 y) 14.4 ······························· 7 分 ··········· ·········· ·········· ·········· ··········· ··········
C D E O B
A
BD ∥ AC BEO ACO 90°
DE EB 1 5 3 BD （cm）············ 分 ··········· 3 ·········· · 2 2
D 30° ··········· ·········· ··········· ····· ·········· ··········· ··········· ···· O 2D 60° ·····································4 分
跳绳 25% 90 80 70 60 50 40 30 20 10 0 80 50 40 30
球类 40%
其它 踢 毽 20% 15%
球类
跳绳
踢毽
其它
类别
图①
第 19 题图
图②
（1）200 ············································ 分 ··········· ·········· ··········· ··········· 2 ·········· ··········· ··········· ·········· · （2）补充图：扇形图中补充的 跳绳 25% ························ 3 分 ··········· ·········· ··· ·········· ··········· ···
二、填空题（每小题 3 分，共 24 分） 9．4 14．216 10．31 15．4 12． y1 y2 13． 3 3 4
三、解答题（每题 8 分，共 16 分） 17．解：原式= 2 1 ( 2 1) ································ 分 ··········· ·········· ·········· 6 ·········· ··········· ·········· = 2 1 2 1 = 2 2 ··········· ··········· ·········· ···· 分 ··········· ·········· ··········· ···· ·········· ··········· ··········· ··· 8
其它 20% ··········································· 4 分 ··········· ·········· ··········· ··········· ·········· ··········· ··········· ·········· · 条形图中补充的高为 50 ···································· 分 ··········· ·········· ··········· ··· 5 ·········· ··········· ··········· ··· （3）54············································ 7 分 ··········· ·········· ··········· ··········· · ·········· ··········· ··········· ·········· ·· （4）解：1860×40%=744（人） ······························ 分 ． ··········· ·········· ········ 9 ·········· ··········· ········ 答：最喜欢“球类”活动的学生约有 744 人． ······················· 分 ······················ 10 ·········· ··········· · 20．解： （1）解法一： （列表法） A盘 B盘 1 2 3 4
1 2 3 4
解法二： （树状图）
和为 0
1 2 3 1 2
1
1 2 3 0 1
1 2 3
2 1 0
1 2 3
3 2 1
··········· ····· 分 ··········· ···· 4 ·········· ····· 由树状图可知：会产生 12 种结果，它们出现的机会相等，其中和为 1 的有 3 种结果．
2009 年抚顺市初中毕业生学业考试 数学试题参考答案及评分标准
（注：本参考答案只给出一种至几种解法（或证法） ，若用其它方法解答正确，可参考 此评分标准相应步骤赋分） 一、选择题（每小题 3 分，共 24 分） 题号 答案 1 A 2 C 3 B 11． (4， 3) 16． 4n1 4 D 5 D 6 C 7 D 8 A