江苏省徐州市区2022—2023学年上学期九年级数学期中检测试题

这是一份江苏省徐州市区2022—2023学年上学期九年级数学期中检测试题，共8页。试卷主要包含了10 18，2分，， 326分，连接OD.，①证明等内容，欢迎下载使用。
2022—2023学年度第一学期期中检测九年级数学参考答案   9．4                10.-1        11.（-2，3）      12.       13. 2    14.   15. 5        16.           17．10       18．  19． 方程化一般形式且正确给1分（1）  ···························································3分 ··························································6分（2）法一：，····················································10分∴，．·····················································12分法二：，（10分）∴，．········································12分法三：，（10分）∴，．········································12分 20．（1）··························································2分（2）把（﹣1，0），（3，0），（0，3）代入抛物线中得中·····························································4分·································································7分（3）①···························································8分   ②-5≤y≤4·····················································10分    21．（1）见下图（有字母和关键格点即可）， (4分)   32·······················6分（2）见下图（有字母和关键格点即可），（10分）   ······················12分         22．（1）矩形ABCD， AB=xBC=·················1分由题意，得 ．·························3分解得 ，． 当． 当····························································5分答：此时x的值为6 m．············································6分（2）设矩形养殖场的面积为·········································7分由（1）得，···················································10分····························································11分答:当························································12分 23．(1)连接OD.  ∵OA= OD，∴∠OAD=∠ODA  ∵EF垂直平分线交BD，∴DE=BE ∴∠EDB=∠B ·····························3分∵∠C=90°，∴∠OAD +∠B= 90º ∴∠ODA+∠EDB =90°·················································4分∵∠ADB=180°∴∠ODE= 180°-90°=90°∴OD⊥DE ∵OD为半径∴DE是⊙O的切线····················································6分(2) 连接OE，设DE=x由题意，DE=BE=x，∵AC=6，BC=8，OA=2∴OA=OD=2,OC=4，CE=8-x∵在中，∠OCE=90°，由勾股定理得 ∴， ∵在中，∠ODE=90°，由勾股定理得 ∴， ····························································10分∴，x=，答：DE的长为·····················································12分24．（1）（方法不唯一）设抛物线的表达式为，由题意得：，把点B的坐标为（-3，0），点C（0，﹣3）代入得：，(4分)解得：，(5分)∴抛物线的解析式为；·························6分（2）（方法不唯一）过点D作 DH⊥y轴由题意，DH=1,BO=3,OC=3,CH=1,OH=4,··········································8分 , ∴········································11分（3）·····································14分 25．（1）①证明：∵AB＝BC，∴∠ADB＝∠CDB，··················································2分∴DB平分圆周角∠ADC，∴圆中存在“爪形D”；···············································4分②延长DC至点E，使得CE＝AD，连接BE， 5分∵∠A＋∠DCB＝180°∠ECB＋∠DCB＝180°∴∠A＝∠ECB∵CE＝AD，AB＝BC∴△BAD≌△BCE∴∠E＝∠ADB， BE＝BD······················8分∵∠ADC＝90°，∠ADB＝∠CDB∴∠E＝∠ADB＝45° ∴△BDE为等腰直角三角形····················10分∴由勾股定理得，，即, ∴CE+CD=AD+CD=··························12分 （2）120°··································14分