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如图,⊙O的半径OC=5cm,直线L⊥OC,垂足为H,且L交⊙O于A,B两点,A...
如图,⊙O的半径OC=5cm,直线L⊥OC,垂足为H,且L交⊙O于A,B两点,AB=8cm,则L沿OC所在直线向下平移( )cm时与⊙O相切.
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A.1
B.2
C.3
D.4
考点分析:
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