练习册

  • 练习册
  • 试题
    28．如图(18).在平面直角坐标系中.的边在轴上.且.以为直径的圆过点．若点的坐标为..A.B两点的横坐标.是关于的方程的两根． (1)求.的值, (2)若平分线所在的直线交轴于点.试求直线对应的一次函数解析式, (3)过点任作一直线分别交射线.(点除外)于点.．则的是否为定值?若是.求出该定值,若不是.请说明理由． 28．解:(1)以为直径的圆过点. .而点的坐标为. 由易知. .····································································································· 1分 即:.解之得:或． .. 即．···································································································· 2分 由根与系数关系有: . 解之.．································································································ 4分 .过点作.交于点. 易知.且. 在中.易得.··········· 5分 . . 又.有. .······································································································· 6分 . 则.即.························································································ 7分 易求得直线对应的一次函数解析式为:．··················································· 8分 解法二:过作于.于. 由. 求得．········································································································ 5分 又. 求得．····························································································· 7分 即. 易求得直线对应的一次函数解析式为:．··················································· 8分 (3)过点作于.于． 为的平分线.． 由.有········································································· 9分 由.有······································································ 10分 .··············································································· 11分 即．···················································································· 12分 【查看更多】

     

    题目列表(包括答案和解析)

    （2013•香坊区二模）如图，在平面直角坐标系中，O为坐标原点，直线y=x+4与x轴交于点A，与y轴交于点B，点C在x轴负半轴上，S△ABC=28．点P从C出发沿CA向终点A运动，设P点坐标为（t，0）．
    （1）求直线CB的解析式；
    （2）连接BP，分别过点A、C向直线BP作垂线，垂足分别为E、F，线段EF的垂直平分线交AC于点G，连接BG，求BG的长；
    （3）在（2）的条件下，当∠BGA=2∠PBG时，求P点坐标．

    查看答案和解析>>

    如图，在平面直角坐标系中，O为坐标原点，直线y=x+4与x轴交于点A，与y轴交于点B，点C在x轴负半轴上，S△ABC=28．点P从C出发沿CA向终点A运动，设P点坐标为（t，0）．
    （1）求直线CB的解析式；
    （2）连接BP，分别过点A、C向直线BP作垂线，垂足分别为E、F，线段EF的垂直平分线交AC于点G，连接BG，求BG的长；
    （3）在（2）的条件下，当∠BGA=2∠PBG时，求P点坐标．

    查看答案和解析>>

    (2006黑龙江课改，28)(10分)如图，在平面直角坐标系中，点A、B分别在x轴、y轴上，线段OA、OB的长(OA＜OB)是方程的两个根，点C是线段AB的中点，点D在线段OC上，OD=2CD．

    (1)求点C的坐标；

    (2)求直线AD的解析式；

    (3)P是直线AD上的点，在平面内是否存在点Q，使以O、A、P、Q为顶点的四边形是菱形？若存在，请直接写出点Q的坐标；若不存在，请说明理由．

    查看答案和解析>>

    精英家教网如图，在平面直角坐标系中，矩形OABC的顶点A（0，3），C（-1，0），将矩形OABC绕原点顺时针旋转90°，得到矩形OA′B′C′．设直线BB′与x轴交于点M、与y轴交于点N，抛物线y=ax2+2x+c的图象经过点C、M、N．解答下列问题：
    （1）分别求出直线BB′和抛物线所表示的函数解析式；
    （2）将△MON沿直线MN翻折，点O落在点P处，请你判断点P是否在抛物线上，说明理由；
    （3）将抛物线进行平移（沿上下或左右方向），使它经过点C′，求此时抛物线的解析式．

    查看答案和解析>>

    如图，在平面直角坐标系中，已知点A（3，2）和点B（5，0），试求sin∠AOB和tan∠ABO的值．

    查看答案和解析>>


    同步练习册答案