问题
选择题
若⊙O的直径为20cm，点O到直线l的距离为10cm，则直线l与⊙O的位置关系是
A．相交
B．相切
C．相离
D．无法确定
答案
B.
题目分析：∵⊙O的直径为20cm，
∴⊙O的半径为10cm，
∵圆心O到直线l的距离是10cm，
∴根据圆心距与半径之间的数量关系可知直线l与⊙O的位置关系是相切．
故选B．
考点: 直线与圆的位置关系．
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若⊙O的直径为20cm，点O到直线l的距离为10cm，则直线l与⊙O的位置关系是
A．相交
B．相切
C．相离
D．无法确定
B.
题目分析：∵⊙O的直径为20cm，
∴⊙O的半径为10cm，
∵圆心O到直线l的距离是10cm，
∴根据圆心距与半径之间的数量关系可知直线l与⊙O的位置关系是相切．
故选B．
考点: 直线与圆的位置关系．
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