(类比探究)如图1,线段AD,CB相交于点O,连接AB,DC,我们把形如图1的图形称之为“X型”.如图2,在图1的条件下,∠DAB和∠BCD的平分线AE和CE相交于点E,并且与CB,AD分别相交于F,G,试解答下列问题:
(1)在图1中,请直接写出∠A,∠B,∠C,∠D之间的数量关系:____________;
(2)在图2中,共有______个“X型”;
(3)在图2中,若∠D=40°,∠B=30°,则∠AEC=_______;
(4)在图2中,若∠D=α,∠B=β,则∠AEC=__________.
(1)在图1中,请直接写出∠A,∠B,∠C,∠D之间的数量关系:____________;
(2)在图2中,共有______个“X型”;
(3)在图2中,若∠D=40°,∠B=30°,则∠AEC=_______;
(4)在图2中,若∠D=α,∠B=β,则∠AEC=__________.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/21/233bc246-4dab-496f-ac93-197d2e792f36.png?resizew=303)
19-20七年级下·河南新乡·期末 查看更多[3]
河南省新乡市辉县市2019-2020学年七年级下学期期末数学试题(已下线)专题10 8字型+角分线求角-【微专题】2022-2023学年八年级数学上册常考点微专题提分精练(人教版)(已下线)专题12 8字型中的角平分线综合问题-【微专题】2022-2023学年七年级数学下册常考点微专题提分精练(苏科版)
更新时间:2020-06-25 12:17:09
|
相似题推荐
解答题-计算题
|
适中
(0.65)
【推荐1】如图1是一个五角星.
(1)计算:∠A+∠B+∠C+∠D+∠E的度数.
(2)当BE向上移动,过点A时,如图2,五个角的和(即∠CAD+∠B+∠C+∠D+∠E)有无变化?说明你的理由.
(3)如图3,把图2中的点C向上移到BD上时,五个角的和(即∠CAD+∠B+∠ACE+∠D+∠E)有无变化?说明你的理由.
(1)计算:∠A+∠B+∠C+∠D+∠E的度数.
(2)当BE向上移动,过点A时,如图2,五个角的和(即∠CAD+∠B+∠C+∠D+∠E)有无变化?说明你的理由.
(3)如图3,把图2中的点C向上移到BD上时,五个角的和(即∠CAD+∠B+∠ACE+∠D+∠E)有无变化?说明你的理由.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/5/27/3875ca50-6f36-4b1f-a0c5-df16823cd629.png?resizew=451)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐2】如图①,线段
,
相交于点
.
(1)求证:
;
(2)如图②,线段线段
,
相交于点
,
和
的角平分线相交于点
,
,
相交于点
,
,
相交于点
,若
,
,请结合(1)中的结论,求
的度数.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/29/f4e24b62-9f7d-4202-a123-98f10c693e5f.png?resizew=266)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f9d0a0a22737590ac049c49da6de2c38.png)
(2)如图②,线段线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdb8eca20ce2c918ea4034ea15210c7f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a9fe609f7851c20ad9a6892f080a0ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d777d15cd733338ecfd0ea63819f62c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/691048ce61c91a8a3680fa3025193160.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b871a762469393cdd22f15aa49ebb8f9.png)
您最近一年使用:0次