Question

圓是________圖形，直徑所在的直線是圓的________，圓有________條對(duì)稱軸．

Answer 1

軸對(duì)稱    對(duì)稱軸    無數(shù)
分析：根據(jù)軸對(duì)稱圖形的意義：如果一個(gè)圖形沿著一條直線對(duì)折后兩部分完全重合，這樣的圖形叫做軸對(duì)稱圖形，這條直線叫做對(duì)稱軸；由此可知：圓是軸對(duì)稱圖形，任何-條直徑所在的直線都是圓的對(duì)稱軸，圓有無數(shù)條對(duì)稱軸．
解答：圓是軸對(duì)稱圖形，直徑所在的直線都是圓的對(duì)稱軸，圓有無數(shù)條對(duì)稱軸；
故答案為：軸對(duì)稱，對(duì)稱軸，無數(shù)．
點(diǎn)評(píng)：此題考查了圓是軸對(duì)稱圖形，圓有無數(shù)條對(duì)稱軸．