山东省济南市高新区2020-2021学年八年级上学期期中考数学试题（扫描版）

第 1页（共 5页） 2020 至 2021 学年第一学期期中学业水平测试 高新初中数学八年级参考答案及评分标准 一、选择题 题号 1 2 3 4 5 6 7 8 9 10 11 12 答案 C A C C C A C A B D B A 二、填空题:（本大题共 6 个小题，每小题 4 分，共 24 分．） 13． (3,2) 14．3 15．7.5 16． 3 17．1 18．（ � � ，0） 三、解答题:（本大题共 12 个小题，共 78 分．解答应写出文字说明、证明过程或演算步骤．） 19．（本题 6 分） 解：原式= 3222332  ··························································································4 分 ＝ 323  ··········································································································6 分 20．（本题 6 分） 解：原式= 26232-3  ································································································5 分 = 626  ············································································································6 分 21．（本题 6 分） 解： 2 3 3 5 11 x y x y      ① ② ， ① 5  ②得：13 26x  ， 解得： 2x  ·····················································································································3 分 把 2x  代入①得： 4 3y  ， 解得： 1y   ···················································································································5 分 所以方程组的解是 2 1 x y     ··································································································6 分 22．（本题 8 分） 解：（1）为 ·················································································································2 分 （2）为： 5 ·················································································································4 分 (3) ····················································································································6 分 （4） ················································································8 分 第 2页（共 5页） 23．（本题 8 分） 解：（1） 6 7 或 7 6 ； 6 7 或 7 6 ； 7 6 ····················································3 分 （2）原式 2( 5 3)  ·····································································································6 分 5 3  ··················································