题目

如图，把长方形纸片ABCD折叠，使顶点A与顶点C重合在一起，EF为折痕．若AB=9，BC=3，试求以折痕EF为边长的正方形面积（ ）A. 11 B. 10 C. 9 D. 16 答案：【答案】B【解析】根据矩形和折叠性质可得△EHC≌△FBC，从而可得BF=HE=DE，设BF=EH=DE=x，则AF=CF=9﹣x，在Rt△BCF中，由BF2+BC2=CF2可得BF=DE=AG=4，据此得出GF=1，由EF2=EG2+GF2可得答案．如图，∵四边形ABCD是矩形，∴AD=BC，∠D=∠B=90°，根据折叠的性质，有HC=AD，∠H=∠D，HE=DE，∴HC=BC，∠H=∠B，又∠HCE+∠ECF=90°，∠D根据材料内容，从下面五个选项中选出能填入文中空缺处的最佳选项，使短文意思通顺、内容完整，并将其标号填写在下面题号后的横线上。Do you have any idols? Have you ever dreamed of meeting a famous actor or talking with a superstar, even having dinner with him? In Britain, some people say they would do anything a famous person they loved asked them to do! One in three people in Britain have a new kind of disease. 1 Some people love famous stars like Britney Spears, David Beckham or even Tony Blair. It is not just the young. 2 One in four people are so interested in their heir that it affects their life. There are two ways of worshipping(崇拜) famous people. One way is just to follow them or talk about them with friends for fun. 3 People have very strong feelings for them and think they are their friends. This is not normal and is an illness. Experts report there are both good and bad sides of loving someone famous. 4 However. those who have strong feelings for a famous person are perhaps to feel more lonely and worried. "Worshipping famous people is not certainly a bad thing. 5 " Dr. John, an expert said.根据材料内容，从下面五个选项中选出能填人文中空缺处的最佳选项，使短文意思通顺，内容完整，并将其标号填涂在答题卡相应位置。A. The other is a more serious way.B. Crown-ups have the same problemC. They love a famous person too much.D. But overdoing it may not always be good for you.E. People who do so for fun are found to be happier.