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如图,在△ABC中,∠A=70°,∠B=55°,以BC为直径作⊙O,分别交AB、AC于点E、F,则的度数为 °.
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如图在△ABC中BD平分∠ABCBC的垂直平分线交BC于点E.交BD于点F.连结CF.若∠
=60°,∠ACF =45°,则∠ABC的度数为( )
A.45°
50°
55°
60°
.如图在等边△ABC中D.为BC边上一点E.为AC边上一点且∠ADE=60°BD=3CE=2则△AB
9
12
15
18
如图在△ABC中AB=ACD.为BC中点∠BAD=35°则∠C.的度数为
35°
45°
55°
65°
如图点D.是△ABC的边BC延长线上的一点∠A=70°∠ACD=105°则∠B=
55°
65°
45°
35°
如图11AD⊥BC于点D.D.为BC的中点连接AB∠ABC的平分线交AD于点O.连接OC若∠AOC=
如图在△ABC中AB=ACD.为BC中点∠BAD=35°则∠C.的度数为
35°
45°
55°
60°
如图在△ABC中AB=AC点D.在AC边上且BD=BC=AD则∠
的度数为( ) A. 30°
36°
45°
70°
如图在△ABC中∠ABC=50°∠ACB=60°点E.在BC的延长线上∠ABC的平分线BD与∠ACE
∠BAC=70°
∠DOC=90°
∠BDC=35°
∠DAC=55°
如图所示△ABC平移得到△DEF若∠DEF=35°∠ACB=70°则∠
的度数是( )
A.55°
65°
75°
85°
如图△ABC中已知∠C.=90°∠B.=55°点D.在边BC上BD=2CD.把△ABC绕着点D.逆时
70°
70°或120°
120°
80°
已知如图在平面上将△ABC绕B.点旋转到△A.’BC’的位置时AA’∥BC∠ABC=70°则∠ABC
如图△ABC中已知∠C.=90°∠B.=55°点D.在边BC上BD=2CD.把△ABC绕着点D.逆时
70°
70°或120°
120°
80°
如图在△ABC中点D.E.F.分别在边BC.AB.AC上且BD=BECD=CF∠
=70°,那么∠FDE等于( )
A.40°
45°
55°
35°
如图在△ABC中点D.E.F.分别是ABACBC的中点若△ABC的周长为12cm则△DEF的周长是c
如图在△ABC中∠B.=30°∠C.=70°AD是△ABC的一条角平分线则∠CAD的度数为
40°
45°
50°
55°
如图在△ABC中∠B.=67°∠C.=33°AD是△ABC的角平分线则∠CAD的度数为
40°
45°
50°
55°
如图在△ABC中已知∠B.和∠C.的平分线相交于点D.过点D.作EF∥BC交AB.AC于点E.F.若
18
17
16
15
如图BD平分∠ABCCD⊥BDD为垂足∠C.=55°则∠ABC的度数是
35°
55°
60°
70°
如图△ABC中AB=AC=10BC=8AD平分∠BAC交BC于点D.点E.为AC的中点连接DE则△C
20
12
14
13
如图在△ABC中点D.E.F.分别在边BC.AB.AC上且BD=BECD=CF∠A=70°那么∠FD
40°
45°
55°
35°
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