问题
填空题
△ABC中，AB=5，AC=9，则BC边上的中线AD的长的取值范围是______．
答案
延长AD到E，使DE=AD，连接CE，
∵AD=DE，∠AOB=∠EOC，BD=CD，
∴△ABD≌△ECD，
∴EC=AB=5，
△AEC中
∵9-5=4，9+5=14，∴4＜2AD＜14，
∴2＜AD＜7．
故填2＜AD＜7．
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△ABC中，AB=5，AC=9，则BC边上的中线AD的长的取值范围是______．
延长AD到E，使DE=AD，连接CE，
∵AD=DE，∠AOB=∠EOC，BD=CD，
∴△ABD≌△ECD，
∴EC=AB=5，
△AEC中
∵9-5=4，9+5=14，∴4＜2AD＜14，
∴2＜AD＜7．
故填2＜AD＜7．
I like all kinds of chocolate, especially bitter chocolate. So when Mother had bought one, I couldn’t help thinking about 36 . I was helping Father in the yard when suddenly I got an idea. I could cut a piece 37 that chocolate without anyone knowing it. I waited 38 Mother went outside feeding the chickens. Then I told Father I wanted to go for a drink of water. I went into the room and got the 39 down. Just when I had the knife ready to cut, I heard Mother coming. So I had to put the chocolate 40 into my shirt, went to my mom and 41 the chocolate there. And then I went back to 42 Father. All the rest of the afternoon, I didn’t dare to look at Father. Every time he spoke, it made me jump. My hands began shaking and my heart started 43 fast. I didn’t want the chocolate any more. I 44 wanted to get a chance to put it back. Have you ever had a similar 45 ?
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