黑龙江省绥化市望奎县2023-2024学年八年级下学期5月期中考试数学试题

班级姓名考班级姓名考号8.已知SKIPIF1<0是正比例函数，则m的值是()A.8

B.4

C.±3

D.39．如图所示，在四边形ABCD中，AD∥BC，要使四边形ABCD成为平行四边形还需要条件（）SHAPEA．AB=DCB．∠1=∠2C．AB=ADD．∠D=∠B10、下列四幅图像近似刻画了两个变量之间的关系，图像与下列四种情景对应排序正确的是(

)①一辆汽车在公路上匀速行驶(汽车行驶的路程与时间的关系)；②向锥形瓶中匀速注水(水面的高度与注水时间的关系)；③将常温下的温度计插入一杯热水中(温度计的读数与时间的关系)；④一杯越来越凉的水(水温与时间的关系).A.①②④③

B.③④②①

C.①④②③

D.③②④①11．如图，周长为16的菱形ABCD中，点E，F分别在AB，AD边上，AE=1，AF=3，P为BD上一动点，则线段EP+FP的长最短为（）A．3B．4C．5D．69题图11题图填空题（共30分）12.要使二次根式有意义,则的取值范围是________．13.已知平行四边形ABCD中,∠A+∠C＝200°,则∠B的度数是____．◆年级试题第2页（共8页）××年级××试题第1页（共8页）选择题（30分）（共33分）1．下列的式子一定是二次根式的是（）A．B．C．D．2．在下列四组线段中，能组成直角三角形的是（）A．a=32，b=42，c=52B．a=11，b=12，c=13C．a=9，b=40，c=41D．a：b：c=1：1：23．如图，每个小正方形的边长为1，A、B、C是小正方形的顶点，则∠ABC的度数为（）3题图A．90°B．60°C．45°D．30°4．下列变形中，正确的是（）A．（2）2=2×3=6B．=﹣C．=D．=5．直角三角形中，两直角边分别是12和5，则斜边上的中线长是（）A．34B．26C．8.5D．6.56．顺次连结菱形四边中点所得的四边形一定是（）A．平行四边形B．矩形C．菱形D．正方形7.在平行四边形ABCD中，∠A：∠B：∠C：∠D的值可以是（）A.1：2：3：4B.1：2：2：1C.1：2：1：2D.1：1：2：2△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△装订线学校班级年班姓名考号2023-2024学年度第二学期期中考试初三年级数学试题温馨提示：1.考试时间为120分钟。2.全卷共有三道大题，总分为120分。题号一二三四五六七总分得分114.如图,矩形ABCD的对角线AC,BD交于点O,AC＝4cm,∠AOD＝120°,则BC的长为_____cm．15.如图所示,所有的四边形都是正方形,所有的三角形都是直角三角形,其中最大的正方形的边长为7cm,正方形A,B,C的面积分别是8cm2,10cm2,14cm2,则正方形D的面积是__________cm2．16.如图,将平行四边形ABCO放置在平面直角坐标系xOy中,O为坐标原点,若点A的坐标是（8,0）,点C的坐标是（2,6）,则点B的坐标是___________.17.如图,□ABCD的对角线相交于点O,两条对角线的和为18,AD的长为5,则△OBC的周长为___________．年级试题第3页（共8页）年级试题第4页（共8页）18．若直角三角形两直角边的比为3：4，斜边长为20，则此直角三角形的周长为19．若菱形的两条对角线长分别是6和8，则此菱形的周长是，面积是．20.如图，ABCD是对角线互相垂直的四边形，且OB=OD,请你添加一个适当的条件____________,使ABCD成为菱形.（只需添加一个即可）21.如图，在直角坐标系中，已知点A（﹣3，0）、B（0，4），对△OAB连续作旋转变换，依次得到△1、△2、△3、△4…，则△2013的直角顶点的坐标为．21题图20题图三、解答题（共57分）22计算.（8分）（1）（2）：()()△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△装订线2323.（8分）如图8，四边形ABCD是菱形，对角线AC与BD相交于O,AB=5,AO=4,求BD的长.24.（8分）已知a=，b=，求a2+b2﹣ab的值．25（8分）.已知正比例函数y=kx图象经过点（3，﹣6），求：（1）这个函数的解析式；（2）判断点A（4，﹣2）是否在这个函数图象上；（3）图象上两点B（x1，y1）、C（x2，y2），如果x1＞x2，比较y1，y2的大小.26.（8分）如图，在平行四边形ABCD中，对角线AC,BD交于点O,经过点O的直线交AB于E，交CD于F.求证：OE=OF.年级试题第6页（共8页）年级试题第5页（共8页）△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△装订线班级班级姓名考号227.（8分）如图，在四边形ABCD中，AB=BC，对角线BD平分ABC，P是BD上一点，过点P作PMAD，PNCD，垂足分别为M、N。(1)求证：ADB=CDB；(2)若ADC=90，求证：四边形MPND是正方形。年级试题第7页（共8页）年级试题第8页（共8页）28.（9分）如图，在等边三角形ABC中，BC=6cm.射线AG//BC，点E从点A出发沿射线AG以1cm/s的速度运动，同时点F从点B出发沿射线BC以2cm/s的速度运动，设运动时间为t(s).（1）连接EF，当EF经过AC边的中点D时，求证：△ADE≌△CDF；（2）填空：①当t为_________s时，四边形ACFE是菱形；②当t为_________s时，以A、F、C、E为顶点的四边形是直角梯形.△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△△