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(2009•西宁)身边没有量角器时,怎样得到一些特定度数的角呢?动手操作有时可以...
(2009•西宁)身边没有量角器时,怎样得到一些特定度数的角呢?动手操作有时可以解“燃眉之急”.如图,已知矩形纸片ABCD(矩形纸片要足够长),我们按如下步骤操作可以得到一个特定的角:
(1)以点A所在直线为折痕,折叠纸片,使点B落在AD上,折痕与BC交于E;
(2)将纸片展平后,再一次折叠纸片,以E所在直线为折痕,使点A落在BC上,折痕EF交AD于F.
则∠AFE=( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131019110506256090366/SYS201310191105062560903010_ST/images0.png)
A.60°
B.67.5°
C.72°
D.75°
考点分析:
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