Maths problem: how to do, thanks.?

Question

Answer 1

最愛解答

△FBC 等邊, 故等角, 故 ∠FBC = 60°

□ABCD 是正方形, 所以 ∠ABF = 30°.

BF = BC = BA,

所以 △BFA 等腰,

∴ ∠AFB = ∠FAB = (180°-30°)/2 = 75°

∴ ∠AFE = 180° - 60° - 75° = 45°