Question

如图，△ABC与△DEF是位似图形，位似比为2：3，已知AB=4，则DE的长等于（　　）               

                                                                          

A．6                            B．5                            C．9                            D．

Answer 1

A【考点】位似变换．                                                                        

【分析】位似是特殊的相似，位似比就是相似比，相似形对应边的比相等．                 

【解答】解：根据题意，△ABC与△DEF位似，且AB：DE=2：3，AB=4              

∴DE=6                                                                                              

故选A．                                                                                            

【点评】本题就是考查位似的定义，是相似的性质的一个简单应用．