(2009•杭州)如图,已知线段a.
(1)只用直尺(没有刻度的尺)和圆规,求作一个直角三角形ABC,以AB和BC分别为两条直角边,使AB=a,BC=
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a(要求保留作图痕迹,不必写出作法);
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(2)若在(1)作出的Rt△ABC中,AB=4cm,求AC边上的高.
考点分析:
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