> Hi, > > I've some troubles trying to prove this problem: > > Given a square (ABCD) , E is an internal point to the > square such that the angle ECD = angle EDC = 15°; > prove that ABE is an equilateral triangle. > > I've just managed to prove that ABE is isosceles, but > can't move forward. Hope someone can help me figure > out the right path!
Hi,GabMat, I have a solution to your problem. Hope you are aware of the basic Trigonometry principles and the sine rule which states that- In ?ABC a/sinA=b/sin B=c/sin C. You can find my solution in the attachments because it is difficult to type it. Let me know about it.