Decide how big the unmarked angles are.
Please enable Java for an interactive construction (with Cinderella).
Angle CDE is
Choose...
30
40
50
60
70
75
80
110
130
140
150
Angle AED is
Choose...
30
40
50
60
70
75
80
110
130
140
150
Angle DFE is
Choose...
30
40
50
60
70
75
80
90
100
140
150
Decide how big the unmarked angles are.