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歡迎您訪問數學考題練習:如圖,將矩形ABCD沿EF折疊,C點落在C′處!

數學考題練習:如圖,將矩形ABCD沿EF折疊,C點落在C′處

更新時間:2024-01-12 12:58:55作者:貝語網校

如圖,將矩形ABCD沿EF折疊,C點落在C′處,D點落在D′處,若∠EFC=110°,則∠BF C′=

A.40°

B.50°

C.60°

D.70°

試題答案

A

試題解析

首先根據折疊可以得到∠EFC=∠EFC′=110°,同時根據已知條件可以求出∠EFB的度數,接著就可以求出∠BF C′的度數.

解答:由折疊得:

∠EFC=∠EFC′=110°,

∴∠EFB=180°-110°=70°,

∴∠BF C′=∠EFC′-∠EFB=40°.

故選A.

點評:本題考查圖形的折疊與拼接,同時考查了三角形的幾何基本知識,解題時應分別對每一個圖形進行仔細分析,難度不大

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