在平面内有线段AB和直线l，点A、B到直线l的距离分别是4cm、6cm．_爱下问搜题

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问题填空题

在平面内有线段AB和直线l，点A、B到直线l的距离分别是4cm、6cm．则线段AB的中点C到直线l的距离______．

答案

若AB在直线l的同侧，则CG为梯形ADEB的中位线．

∴CG=

1

2

（AD+BE）=

1

2

×（4+6）=5（cm）；

若AB在直线l的异侧，

连接AE，BD．

向两方延长HC分别交AE，BD于G，F．

则GF=

1

2

（AD+EB）=

1

2

×（4+6）=5cm．

∵C为AB的中点，CH⊥DE，

∴HG，CF分别为△ADE与△BAD的中位线，

∴HG=CF=

1

2

AD=

1

2

×4=2．

∴CH=GF-HG-CF=5-2-2=1（cm）．

线段AB的中点C到直线l的距离5cm或1cm．

简答题

你是如何理解没有正义的制度就没有真正的公平？

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问答题

I agree to some extent with my imaginary English reader. American literary historians are perhaps prone to view their own national scene too narrowly, mistaking prominence for uniqueness. They do over phrase their own literature, or certainly its minor figures. And Americans do swing from aggressive over phrase of their literature to an equally unfortunate, imitative deference. But then, the English themselves are somewhat insular in their literary appraisals. Moreover, in fields where they are not preeminent—e.g. in painting and music—they too alternate between boasting of native products and copying those of the Continent. How many English paintings try to look as though they were done in Paris; how many times have we read in articles that they really represent an "English tradition" after all.