vndnjn wrote:
In quadrilateral, ABCE: sum of all angles = 360°
90° + 90° + 150° + ∠D = 360°
∠D = 30°
∆CED is isosceles, CE = CD and ∠E = ∠D = 30°
You said CED is isosceles, so CE = CD. How does one reach this conclusion? Can't ED=CD?
The problem I'm having here is that ∆CDE, while isosceles can be 30-30-120 or 75-75-30.
This means our desired angle ∠CED will either be 30 or 75.
Please tell me where I am going wrong. Thank you!