问题
填空题
△ABC中,已知B、C的坐标分别为(-3,0)和(3,0),且△ABC的周长等于16,则顶点A的轨迹方程为______.
答案
由题意可得 AB+AC=10>BC,故顶点A的轨迹是以B、C为焦点的椭圆,除去与x轴的交点.
∴2a=10,c=3∴b=4,故顶点A的轨迹方程为
+x2 25
=1,(y≠0),y2 16
故答案为:
+x2 25
=1,(y≠0).y2 16
△ABC中,已知B、C的坐标分别为(-3,0)和(3,0),且△ABC的周长等于16,则顶点A的轨迹方程为______.
由题意可得 AB+AC=10>BC,故顶点A的轨迹是以B、C为焦点的椭圆,除去与x轴的交点.
∴2a=10,c=3∴b=4,故顶点A的轨迹方程为
+x2 25
=1,(y≠0),y2 16
故答案为:
+x2 25
=1,(y≠0).y2 16
任务性阅读,根据penpal的信息填写表格内容。 | |
I have a penpal. Her name is Mary Smith. She is from Paris, France. She can speak English and French. She is fifteen years old. She is at school from Monday to Friday. She often goes to movies on weekends. Comedies are her favorite movies. At school, she likes math and art. She likes playing volleyball and ping-pong. She likes hamburgers very much. | |
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