题目
题型:不详难度:来源:
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225230-65444.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225230-54233.png)
答案
解析
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225230-77465.png)
∵DE∥BC,
∴△ADE∽△ABC,
∴
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225230-27370.png)
∴
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225231-85906.png)
∴
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225230-77465.png)
∴AC=2cm.
核心考点
举一反三
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225220-15975.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225221-95990.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225221-95990.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225221-86409.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225221-23444.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225221-95990.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225221-90896.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225221-49798.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225222-97358.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225222-59084.png)
(1)写出图1中所有相等的角(直角除外),并给出证明;
(2)若图1中的切线
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225221-23444.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225222-84824.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225222-84824.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225221-95990.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225222-55522.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225222-20092.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225222-15909.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225223-84438.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225223-87696.png)
(3)在图2中,证明:
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225223-38519.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225223-78485.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225223-62776.png)
A.0.5m | B.0.55m | C.0.6m | D.2.2m |
A.3 cm | B.6 cm | C.9cm | D.12cm |
A.![]() | B.![]() | C.![]() | D.![]() |
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225209-63509.png)
(1)当折痕的另一端F在AB边上时,如图(1).求△EFG的面积.
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225202-43557.png)
(2)当折痕的另一端F在AD边上时,如图(2).证明四边形BGEF为菱形,并求出折痕GF的长.
![](http://img.shitiku.com.cn/uploads/allimg/20191102/20191102225202-44919.png)
最新试题
- 1将10.4g两种金属的混合物投入足量的盐酸中,反应完全后,得到氢气5.6L(标准状况),该混合物的组成可能是 [
- 2下列骨的结构中,具有造血功能的结构是( )A.黄骨髓B.红骨髓C.骨松质D.骨密质
- 3已知(m为常数,m>0且m≠1).设(n∈)是首项为m2,公比为m的等比数列.(1)求证:数列是等差数列; (2
- 4【题文】下图中,昼夜温差最小的是:( )
- 5一列简谐横波沿x轴传播,波长为1.2 m,振幅为A。当坐标为x=0处质元的位移为且向y轴负方向运动时,坐标为x="0.4
- 6若,则等于( ) A.B.0C.1D.2
- 7下列离子方程式正确的是[ ]A.水玻璃加盐酸:SiO32-+2H+=H2SiO3↓ B.小苏打和烧碱溶液:HCO
- 8将一生锈的铁片置于稀硝酸中,反应结束后,共收集11.2L NO气体(标况)。溶液中还剩下固体残渣5g,过滤后向浅绿色溶液
- 9已知∠AOB=90°,∠COD=90°,画出示意图并探究∠AOC与∠BOD的关系.
- 10在一个不透明的口袋中,装有若干个除颜色不同其余都相同的球,如果口袋中装有3个红球且摸到红球的概率为,那么口袋中球的总数为
热门考点
- 1下列事件不属于生产资料私有制向生产资料公有制过渡的是: [ ]A、社会主义工业化 B、农业合作化 C、手工业合
- 2He was disappointed that his plan did not____at the meeting.
- 3已知函数f(x)(xR)为奇函数, f(2)="1," f(x+2)=f(x)+f(2),则f(3)等于( )A.B
- 4It’s 8 o’clock in the evening. Tom ______ TV.A.watchB.watche
- 5交流发电机是根据______现象的原理制造的,它所产生的感应电流的方向与线圈的转动方向和______的方向有关.
- 6在没有自由水源的高山上,只给你一个不透水的塑料袋,可利用植物的什么作用取到水( )A.蒸腾作用B.光合作用C.呼吸作用
- 7We all joined the game______ Bill because he was hurt and ha
- 8下列物质的物理性质正确的是( )A.液氧(无色液体)B.高锰酸钾(黑色固体)C.二氧化硫(无色无味气体)D.四氧化三铁
- 9【题文】唐德刚在《晚清七十年》中提出“历史三峡论”,将四千多年来中国政治形态变迁分为封建、帝制和民治三大阶段。其中“封建
- 10如图:BO、CO分别是△ABC两个外角∠CBD和∠BCE的平分线,则∠BOC与∠A的关系是_______________