2020年清远市初中毕业生学业考试数 学 科 试 题说明：1．全卷共4页，考试时间为100分钟，满分120分．2．选择题每小题选出答案后，用2B 铅笔把答题卡上对应题的答案标号涂黑；如需改动，用橡皮擦干净后，再选涂其他答案标号；不能答在试卷上．3．非选择题必须用黑色字迹的钢笔或签字笔作答，涉及作图的题目，用2B 铅笔画图，再用黑色字迹的钢笔或签字笔描黑．答案必须写在答题卡各题指字区域内的相应位置上；如需改动，先划掉原来的答案，然后再写上新的答案；改动的答案也不能超出指定的区域．不准A ．4x =±B ．4x =C ．4x =-D ．16x =7．已知O ⊙的半径r ，圆心O 到直线l 的距离为d ，当d r =时，直线l 与O ⊙的位置关系是（ ）A ．相交B ．相切C ．相离D ．以上都不对 8．计算：()23ab=（ ）A ．22a b B ．23a b C ．26a b D ．6ab9．如图2，AB CD ∥，EF AB ⊥于E EF ，交CD 于F ，已知160∠=°，则2∠=（ ） A ．20° B ．60° C ．30° D ．45°1011121314151617．在“我喜欢的体育项目”调查活动中，小明调查了本班30人，记录结果如下：（其中喜欢打羽毛球的记为A ，喜欢打乒乓球的记为B ，喜欢踢足球的记为C ，喜欢跑步的记为D ）Ａ Ａ Ｃ Ｂ Ａ Ｄ Ｃ Ｃ Ｂ Ｃ Ａ Ｄ Ｄ Ｃ Ｃ Ｂ Ｂ Ｂ Ｂ Ｃ Ｂ Ｄ Ｂ Ｄ Ｂ Ａ Ｂ Ｃ Ａ Ｂ求Ａ的频率．C D B A E F 1 2A B18．计算：201(1)π3--++19．已知图形B 是一个正方形，图形A 由三个图形B 构成，如右图所示，请用图形A 与B 合拼成一个轴对称图形，并把它画在答题卡的表格中．2021α，BC A 图6四、解答题（本大题共4小题，每小题6分，共24分）22．化简：2226926 93 x x xx x x -+-÷-+2324E B A25．已知二次函数2y ax bx c =++中的x y ，满足下表：2627．某饮料厂为了开发新产品，用A种果汁原料和B种果汁原料试制新型甲、乙两种饮料共50千克，设甲种饮料需配制x千克，两种饮料的成本总额为y元．（1）已知甲种饮料成本每千克4元，乙种饮料成本每千克3元，请你写出y与x之间的函数关系式．（2）若用19千克A种果汁原料和17.2千克B种果汁原料试制甲、乙两种新型饮料，下表是试验的相关数据；28CC图92009年清远市初中毕业生学业考试数学试题参考答案及评分标准一、选择题：（每小题3分，共30分）1．A 2．B 3．B 4．A 5．C 6．A 7．B 8．C 9．C 10．D 二、填空题：（每小题3分，共18分）11．6-；12．2；13．6yx=；14．5-；15．14；16．30°三、解答题：（每小题5分，共25分）175分184分5分19202分3分4分5分212分5分224分=(3)(3)22x x xx--⨯=--··················································································6分23．证明：Q四边形ABCD和四边形CEFG都是正方形90CB CD CE CG BCD ECG∴==∠=∠=，，° ···········································3分90BCE DCE∴∠=∠°-90DCG DCE∠=∠°-BCE DCG∴∠=∠···················································································5分CBE CDG∴△≌△ ··················································································6分24．解：画出树状图为：分分25分分分26BC ABOA PO∴=····························································································5分722OB PO==Q，24OA AB∴==，4722BC∴= ······························································································6分开始红红红红红红红红黑黑黑黑黑黑黑黑716827BC BC ∴==， ··········································································· 7分 27．解：（1）依题意得：43(50)150y x x x =+-=+ ··········································· 3分（2）依题意得：0.50.2(50)19(1)0.30.4(50)17.2(2)x x x x +-⎧⎨+-⎩≤…………≤……… ···································· 5分解不等式（1）得：30x ≤解不等式（2）得：28x ≥分分 28分 1216A EF S h S ⎛⎫= ⎪⎝⎭△△ABCC1168242ABC S =⨯⨯=Q △ 22363224122462EFx S x x ⎛⎫- ⎪∴==⨯=-+ ⎪⎪⎝⎭1△A 1122233912241224828A MN A EF y S S x x x x x ⎛⎫=-=--+=-+- ⎪⎝⎭Q △△ 所以 291224(48)y x x x =-+-<< ······················································· 6分 8分。