江苏省南京市建邺区2019-2020学年第一学期九年级数学期末试卷（Word版，含答案）

二、填空题（本大题共 10小题，每小题 2分，共 20分） 7．x1＝0，x2＝2020． 8． 1 4 ． 9．1∶16． 10．6． 11．小林． 12．＞． 13．3π． 14．2∶3． 15．16． 16．α＝β或α＋β＝180°． 三、解答题（本大题共 11小题，共 88分） 17．（本题 6分） 解： x2－4x＋4 ＝ 6＋4． (x－2)2 ＝ 10．·················································································2分 x－2 ＝± 10．·············································································4分 ∴ x ＝± 10＋2． ∴ x1 ＝ 10＋2，x1 ＝－ 10＋2． ···············································6分 （若用公式法解，判别式正确得 2分，代入公式正确得 4分，答案正确得 6分．） 18．（本题 7分） 证明：连接 OC． ····················································································· 1分 ∵ AC ＝ BC， ∴ ∠AOC ＝∠BOC． ·············································································3分 ∵ OC ＝ OC，OD ＝ OE， ∴ △OCD≌△OCE． ··············································································· 6分 ∴ CD ＝ CE． ······················································································· 7分 19．（本题 7分） 解：（1）2．·······························································································2分 （2）图略．·························································································· 5分 （3）x≤－4或 x≥3．············································································· 7分 20．（本题 8分） 解：甲、乙、丙三位同学采用抽签的方式决定出场顺序，所有可能出现的结果有： 题号 1 2 3 4 5 6 答案 A C D C D B A B C D E O 一、选择题（本大题共 6 小题，每小题 2 分，共 12 分） 本评分标准的精神给分． 说明：本评分标准每题给出了一种或几种解法供参考．如果考生的解法与本解答不同，参照 数学试卷参考答案及评分标准 南京九年级建邺区 2019-2020 第一学期期末调研 1 （甲，乙，丙）、（甲，丙，乙）、（乙，甲，丙）、（乙，丙，甲）、（丙，甲，乙）、 （丙，乙，甲）．···················································································· 3分 共有 6种，它们出现的可能性相同．所有的结果中，满足“甲比乙先出场”（记为事 件 A）的结果有 3种，所以 P(A) ＝ 3 6 ＝ 1 2 ．······ ... ...