题目中过A作AF垂直于AE吗,你漏打了?如果是,
AE^2=x^2+9 AF^2=y^2+16 EF^2=x^2+16-8x+9+6y+y^2
AE^2+AF^2=EF^2
轻松解得3y=4x 不能是等腰