Solve this triangle problem

[willbali]

How to find the length DE. ABC is an isoceles triangle with length AB 20 cm
see attached jpg

[Guest]

AE = DE(becasue triangle [tex]AEC \cong DEC[/tex]

[tex]\frac{AE}{EB} = \frac{AC}{BC}[/tex]

[tex]AC = 20[/tex]

[tex]AB^2 = AC^2 + AB^2[/tex]

Is it clear?

[togiap]

your problem don't enough data: What is CE?
Guest's Answer: [tex]{AB}^{2} = {AC}^{2} + AB^{2}[/tex] is false.

[daredman]

Is CE an angle bisector? otherwise there's a missing info

[Guest]

Please help to solve the question!!!
Find the indicated side in the spherical triangle:
a) B= 104 30.7' C= 62 52.1' a=56 6.4' to find c-?
b) A= 116 1.8' B= 103 17.6' C= 94 21.2' to find b-?

Many thanks in advance!

[Dilfanian]

DE=20(2^1/2-1)