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等腰△ABC的底边BC=8cm,腰长AB=5cm,一动点P在底边上从点B开始向点...
等腰△ABC的底边BC=8cm,腰长AB=5cm,一动点P在底边上从点B开始向点C以0.25cm/秒的速度运动,当点P运动到PA与腰垂直的位置时,点P运动的时间应为 秒.
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