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如图,圆上有A,B,C,D四点,其中∠BAD=80度.若,的长度分别为7p,11...
如图,圆上有A,B,C,D四点,其中∠BAD=80度.若
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103101636668606121/SYS201311031016366686061011_ST/0.png)
,
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103101636668606121/SYS201311031016366686061011_ST/1.png)
的长度分别为7p,11p,则
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103101636668606121/SYS201311031016366686061011_ST/2.png)
的长度为何( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103101636668606121/SYS201311031016366686061011_ST/images3.png)
A.4p
B.8p
C.10p
D.15p
考点分析:
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