20 1 1 Analysis of the Third Small Item of Mathematics 23 in Shaoxing Senior High School Entrance Examination
Point D is on the extension line of line BC, so BE= 1 Because AE=2, point D is on the extension line of line CB and the vertical line F of left CD, so triangle ED=EC is an isosceles triangle, because angle ABC equals angle FBE equals 60 degrees, so angle FEB equals 30 degrees, because BE= 1, so FB equals 0.