Can anyone help with a Geometry question?

Question

anonymous · Answer

what is it?

anonymous · Answer

|dw:1421118395563:dw|

mathmate · Answer

ABEC is a kite, so the two diagonals intersect at right angles.
But you need to prove mBD=mCE, right?

mathmate · Answer

Can you prove that $\Delta$ABE is congruent to $\Delta$ACE?

anonymous · Answer

and then say bc is an alt? to get the perp part.  @mathmate

mathmate · Answer

The perpendicular part is a little more complex.
Let the two diagonals of the kite intersect at P.
You need to prove that triangles ABE and ACE are congruent (SSS) therefore PE is an angle bisector.
THEN triangles BEP and CEP are congruent SAS.
Since angles BPE and CPE are congruent and supplementary, perpendicularity follows.
It follows then triangles BDP AND CDP are congruent (SAS) => mBD=mCD.
I'll leave you with writing up the two column proof.

anonymous · Answer

lol i see what u mean there, thx mate :D

mathmate · Answer

You're welcome!  :)