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已知⊙O是△ABC的外接圆,若AB=AC=5,BC=6,则⊙O的半径为( ) A...
已知⊙O是△ABC的外接圆,若AB=AC=5,BC=6,则⊙O的半径为( )
A.4
B.3.25
C.3.125
D.2.25
考点分析:
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