Question

正方形有

4

條對(duì)稱軸，圓有

無(wú)數(shù)

條對(duì)稱軸，平行四邊形有

0

條對(duì)稱軸．

Answer 1

分析：根據(jù)軸對(duì)稱圖形的定義即可解答此類問(wèn)題．

解答：解：根據(jù)軸對(duì)稱圖形的定義可知：正方形的有4條對(duì)稱軸，分別是對(duì)邊中點(diǎn)所在的直線和正方形的對(duì)角線所在的直線；
圓的對(duì)稱軸有無(wú)數(shù)條，分別是經(jīng)過(guò)圓心的直線；
平行四邊形不是軸對(duì)稱圖形，沒(méi)有對(duì)稱軸．
答：正方形有4條對(duì)稱軸，圓形有無(wú)數(shù)條對(duì)稱軸．0
故答案為：4；無(wú)數(shù)；0．

點(diǎn)評(píng)：此題考查了利用軸對(duì)稱圖形的定義確定圖形的對(duì)稱軸的條數(shù)的方法的靈活應(yīng)用．