挑战习题
1/5单选题
难度:

1.

如图,在矩形ABCD中,DE⊥AC于E,∠EDC:∠EDA=1:3,且AC=10,则DE的长度是( )

青果学院


A

3

B

5

C

D

提示1:
PHA+5qC55o2u4oigRURD77ya4oigRURBPTHvvJoz77yM5Y+v5b6X4oigRURDPTIyLjXCsO+8jOKIoEVEQT02Ny41wrA8L3A+
提示2:
PHA+5YaN55SxQUM9MTDvvIzmsYLlvpdERTwvcD4=
正确答案:RA==
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