综合与探究,问题情境:综合实践课上,周老师组织同学们开展了探究三个角之间数量关系的数学活动.已知:
,直线
分别与直线
、
交于点
、
.
(1)如图1,点
在线段
上,
,
,求
的度数;
(2)如图2,
是
的角平分线,
是
的角平分线所在直线,
与
交于点
,试探究
与
的数量关系;
(3)如图3,
平分
,交
于点
,交
于点
,且
:
:
,
,
,求
的度数.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0fff774b4b0087a6f304ce930d359be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d87448e09eaa816e50ae92d111d5ded6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b79dd200766db27fb90d6bd1992cf658.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1ffb98f1e3c1317c0db403d3af04bdc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/8/16/e3e742c5-f316-4864-abe6-1ef363b5a1cb.png?resizew=432)
(1)如图1,点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d87448e09eaa816e50ae92d111d5ded6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7cff5780513b6c12e2c922614645f985.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88003e505289c9a1aecc2a1bab92a739.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e8a16c7d63d2791de54865bf178f70e.png)
(2)如图2,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15bdee7807edba89958c84bf4bb85f15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9f886986096a5a1bfb6fa1cfb17a7bd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eab64bf465405cd87bb03f8cb61cb315.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e61734dbfe998f0fbd192703f021a86b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15bdee7807edba89958c84bf4bb85f15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eab64bf465405cd87bb03f8cb61cb315.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/257f1d3c5a2b24369685557e33c788b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6621d2e9d206a21d17706a7d32c3f8c5.png)
(3)如图3,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/945c016d6c4eb48931946cca7ffd5bdb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68350c3ba1413160eef0f0a4a8cf0c1e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9f79d7939c88e9702962e5917cad290.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf3834d7ec7531f3c3c0ce9b286f7a49.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b51192980a80446658b30110276ce124.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e105760638b22b26ff8bec4354255e4c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be55cea052be3f05c6a868ede321cf8d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dda3b069e9e35893fb756dd18b359ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2ed304e9cfc98635149a00ea292742b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c77a16563686f7055cec388639d1562b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/950275947051d594274525689247ccfd.png)
更新时间:2023-06-14 23:03:18
|
相似题推荐
解答题-问答题
|
较难
(0.4)
【推荐1】已知
,点M、N分别为
上的点,在
之间存在一点P满足
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/2/468afaba-b52c-4156-8212-3f16ba19dd2d.png?resizew=520)
(1)如图1,若
,求
的度数(用含α的代数式表达).
(2)如图2,过点P作
于点H,点E、F在
上,连接
,若
平分
,
平分
,求
与
的数量关系.
(3)在(2)的条件下,若
,求
的度数.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a11029ca6b4b9e7f777af0280cf163c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c28d2790a97390935125aa897417f970.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c28d2790a97390935125aa897417f970.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/568a88f607d69cb5787eff96319f1d89.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/2/468afaba-b52c-4156-8212-3f16ba19dd2d.png?resizew=520)
(1)如图1,若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/548edcb48a64ab7570e9195a39bed656.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7837e6c798eb7a25d890609898432bfe.png)
(2)如图2,过点P作
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20e64f503acd02b53ac2a26b6af3b27b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/272ae10987d437293afe86492cd64339.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc5adb5eb60ae4435a12d93854066298.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1d8d552a601e5c648071c782e7ea054.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fb26d84907c923278ac4626a9d58947.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/828efb8ad6567d9f5ae02b00fb49be6f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dfa70e7c9ef8b856b494d370b7d76482.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c45a8a837c11c07073da3ff751d70278.png)
(3)在(2)的条件下,若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/addf485e509b5365cf552b8b9fa3eb23.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dadaa018a95ded3269d77fa8013019ff.png)
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【推荐2】已知,在平面直角坐标系中,AB⊥x轴于点B,点A
满足![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a6506481b2f6fe12162b3b4a717f96b.png)
,平移线段AB使点A与原点重合,点B的对应点为点C.
(1)则a= ,b= ,点C坐标为 ;
(2)如图1,点D(m,n)在线段BC上,求m,n满足的关系式;
(3)如图2,E是线段OB上一动点,以OB为边作∠BOG=∠AOB,交BC于点G,连CE交OG于点F,当点E在线段OB上运动过程中,
的值是否会发生变化?若变化请说明理由,若不变,请求出其值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/30277e0be448b4955903e81e8795e45d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a6506481b2f6fe12162b3b4a717f96b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d9bb3628bd4f14caaed8988d2639476.png)
(1)则a= ,b= ,点C坐标为 ;
(2)如图1,点D(m,n)在线段BC上,求m,n满足的关系式;
(3)如图2,E是线段OB上一动点,以OB为边作∠BOG=∠AOB,交BC于点G,连CE交OG于点F,当点E在线段OB上运动过程中,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/469cde3fa2f4bb3e815c0a29507f5eaa.png)
![](https://img.xkw.com/dksih/QBM/2021/5/15/2721383006568448/2786938401341440/STEM/ebbf8c61759c47b48a716fddc106efd6.png?resizew=302)
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【推荐1】已知点C在射线OA上.
(1)如图①,CD
OE,若∠AOB=90°,∠OCD=120°,求∠BOE的度数;
(2)在①中,将射线OE沿射线OB平移得O′E'(如图②),若∠AOB=α,探究∠OCD与∠BO′E′的关系(用含α的代数式表示)
(3)在②中,过点O′作OB的垂线,与∠OCD的平分线交于点P(如图③),若∠CPO′=90°,探究∠AOB与∠BO′E′的关系.
(1)如图①,CD
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb31ef428bd9de9bc875b343feded3c7.png)
(2)在①中,将射线OE沿射线OB平移得O′E'(如图②),若∠AOB=α,探究∠OCD与∠BO′E′的关系(用含α的代数式表示)
(3)在②中,过点O′作OB的垂线,与∠OCD的平分线交于点P(如图③),若∠CPO′=90°,探究∠AOB与∠BO′E′的关系.
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【推荐2】如图,直线
,点E、F分别在
上,点M为两平行线内部一点.
的数量关系,并说明理由;
(2)如图2,若
和
的角平分线交于点N,且
,直接利用(1)中的结论,求
的度数;
(3)如图3,点G为直线CD上一点,连接
并延长交直线
于点Q,在线段
上取一点P,连接
,使
,在射线
取一点H,连接
,使
,设
,求
的度数(用含
的代数式表示).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a11029ca6b4b9e7f777af0280cf163c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e85814f051a479a1b04a46f70e96557a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d498c8b2256a00d6928228a855da12f3.png)
(2)如图2,若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0af253831c06acfe352ac7827c08a925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dd4f0048b27e6fb7d233c05011b5b1f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7150ef10e4c0a9551878f05127702855.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a742abf1b0702125a0c77cbfbef118ca.png)
(3)如图3,点G为直线CD上一点,连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e9e953a4a5f98c96bbe67cbaadf76d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67c015d99f2677951bdcd0447240ef93.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fb26d84907c923278ac4626a9d58947.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dbb6748396c5f3422516fdb425566b72.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fb26d84907c923278ac4626a9d58947.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/589786dd7c3a2679c3230b671cd232d6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8eb97ffca2da3fd26ebc21020af979ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9474153b3956117f3b491c62acb5ea1a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d9c1e0c3cab6b7bb3229221f4310ab0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
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名校
【推荐1】探究发现:如图①,在
中,内角
的平分线与外角
的平分线相交于点
.
![](https://img.xkw.com/dksih/QBM/2020/9/27/2558370454044672/2563288590262272/STEM/2acc3ea7-d165-4d61-b3e4-bddc559b9793.png)
(1)若
,则
;
若
,则
;
(2)由此猜想:
与
的关系为 (不必说明理由).
拓展延伸:如图②,四边形
的内角
与外角
的平分线相交于点
,
.
(3)若
,
,求
的度数,由此猜想
与
,
之间的关系,并说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8fabb884dc5f9609de491245463bbe9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/246a86f34603eaf2e6a948681b831b0d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://img.xkw.com/dksih/QBM/2020/9/27/2558370454044672/2563288590262272/STEM/2acc3ea7-d165-4d61-b3e4-bddc559b9793.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a8793053fbb2ac5a3122b092a575124.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b83764876be47a196fd5f408763738a.png)
若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d777d15cd733338ecfd0ea63819f62c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b83764876be47a196fd5f408763738a.png)
(2)由此猜想:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3818a2c9919d358b4c3713396093822b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b871a762469393cdd22f15aa49ebb8f9.png)
拓展延伸:如图②,四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3702b5620dbee356a8e560c78d223ad.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cfc2771aa0d5b97d2297f8a26a6f6b1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/094d11233794245d95ba79128ea3c4b9.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eea89ffbb612f1ed62f68f5a43987b1a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7fb06eb96d88b92689b8a60e4898c30.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50e8c257f5615d30660cef4157c6b273.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50e8c257f5615d30660cef4157c6b273.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3818a2c9919d358b4c3713396093822b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c543c3ddc3723fde6bbfca3ea3b921b.png)
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解答题-证明题
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【推荐2】已知:直线
,M,N分别在直线
,
上,H为平面内一点,连
,
.
至G,
和
的角平分线相交于点E.
①若
,
,则
的度数为 ;
②探究
与
的数量关系,并给予证明;
(2)如图2,
和
的角平分线相交于点E.作
平分
,
交
的延长线于点Q,若
,求
的度数.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0fff774b4b0087a6f304ce930d359be.png)
![](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/b0a8588dc60a543ad70d6bc0d263dbd3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eef1f7b9adab87736321e30949a4d668.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eef1f7b9adab87736321e30949a4d668.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f56df4070fd684f4daa9343d41efe15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a90141185faab937aafd2a072944f697.png)
①若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7eeea7df651b5680359a8d96efd75057.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1cacb02acbd8e8939cf4f9de6b2f06d4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/435f30095577dc714634354f5ad27715.png)
②探究
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/435f30095577dc714634354f5ad27715.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/435f30095577dc714634354f5ad27715.png)
(2)如图2,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f56df4070fd684f4daa9343d41efe15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e764d6c177965e35b04b6ee72cd1576e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/438f34bc8b04e8c494b91306ac6fe352.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d76d1f1c2cccdc00e111e4f37b74459.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7333ee247c008ec32601779c6c5590d2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ce6c0e9de83f2e64ae33609fc08459d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a2692144ab8f4ad063712dec237d182.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae6ee579a2565dae0809c25493243135.png)
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解答题-作图题
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解题方法
【推荐3】(1)如图①,△ABC中,点D、E在边BC上,AE平分∠BAC,AD⊥BC,∠C=40°,∠B=60°,求:
①∠CAE的度数;
②∠DAE的度数.
(2)如图②,若把(1)中的条件“AD⊥BC”变成“F为AE延长线上一点,且FD⊥BC”,其他条件不变,求出∠DFE的度数.
(3)在△ABC中,AE平分∠BAC,若F为EA延长线上一点,FD⊥BC,且∠C=α,∠B=β(β>α),试猜想∠DFE的度数(用α,β表示),请自己作出对应图形并说明理由.
①∠CAE的度数;
②∠DAE的度数.
(2)如图②,若把(1)中的条件“AD⊥BC”变成“F为AE延长线上一点,且FD⊥BC”,其他条件不变,求出∠DFE的度数.
(3)在△ABC中,AE平分∠BAC,若F为EA延长线上一点,FD⊥BC,且∠C=α,∠B=β(β>α),试猜想∠DFE的度数(用α,β表示),请自己作出对应图形并说明理由.
![](https://img.xkw.com/dksih/QBM/2021/3/16/2679067591917568/2679622946390016/STEM/b9202b9a3201437dafc15ed147821856.png?resizew=458)
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【推荐1】如图1:
中,
是高,
是
的平分线,
.
(1)求
的度数
(2)当
,请用
表示
,并写出推导过程
(3)当
是
的外角
的平分线,如图2则此时
的度数是多少,用
表示,直接写出结果.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7cbce11aa19b8bd2bf6ee5a834e005de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3291c5dd7ce3cfff11ae415963f115f.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e37b078d02601f76f0f8320b410809f.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c262288d0311075fef8a5d3083668732.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bfa404d3ff313b0a28a76a48d7d87234.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e37b078d02601f76f0f8320b410809f.png)
(3)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7cbce11aa19b8bd2bf6ee5a834e005de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b400a6c61254b81d4ccc5a2a7cf4c967.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e37b078d02601f76f0f8320b410809f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4e288596fa3811dd2c17bded60e82e7.png)
![](https://img.xkw.com/dksih/QBM/2018/11/16/2077044148723712/2078317232168960/STEM/a342ecc34cff4db59463b1a302a4e81d.png?resizew=102)
![](https://img.xkw.com/dksih/QBM/2018/11/16/2077044148723712/2078317232168960/STEM/9af5cc9d62f74e0182baa98658032fdc.png?resizew=117)
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【推荐2】小明在学习中遇到这样一个问题:如图1,在
中,
,
平分
于D,猜想
之间的数量关系.
(1)小明阅读题目后,没有发现数量关系与解题思路,于是尝试代入
的值求
值,得到下面几组对应值:
上表中
______,于是得到
之间的数量关系为______.
(2)小明继续探究,如图2,在线段AE上任取一点P,过点P作
于点D,请尝试写出
之间的数量关系,并说明理由.
(3)小明突发奇想,交换B、C两个字母位置,如图3,过
的延长线上一点F作
交
的延长线于点D,当
时,
度数为______°.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce6f337c00a6d4bf1e7580d8888db3d6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eca2959143c4fde326b455d38a708e33.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb2d5ad38c799a91070da64c999d0eff.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/9/12/c30e837d-592e-4a19-b85e-6ef4388931ec.jpg?resizew=455)
(1)小明阅读题目后,没有发现数量关系与解题思路,于是尝试代入
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6fbe6460d395de7ca4c1f053aba1371.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e37b078d02601f76f0f8320b410809f.png)
![]() | 10 | 30 | 30 | 20 | 20 |
![]() | 70 | 70 | 60 | 60 | 80 |
![]() | 30 | a | 15 | 20 | 30 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/380bbacf854e30e2e747fc286d2b9997.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb2d5ad38c799a91070da64c999d0eff.png)
(2)小明继续探究,如图2,在线段AE上任取一点P,过点P作
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c65334978b0519b379910dfc4acf8344.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/463d56ab2c3a05550a81478f3c3550cb.png)
(3)小明突发奇想,交换B、C两个字母位置,如图3,过
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1642eec556eb252de9c1ab7bb5ca90b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c4567ae3f7827588855f39569d4f7c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b1bd1adfe4cc6566218f19970c2fd3b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b3105dbb21ffb5730da37a2ffc572b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50e8c257f5615d30660cef4157c6b273.png)
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