Please help I'm having a lot of trouble here!
A student made the table below to show the steps to prove that DC is equal to EC:

Statements Justifications

DC = EC
CPCTC

Question

Please help I'm having a lot of trouble here!
A student made the table below to show the steps to prove that DC is equal to EC:


Statements	Justifications

DC = EC
CPCTC

anonymous · Answer

attachment

anonymous · Answer

@Hero @Kainui

anonymous · Answer

@Michele_Laino

michele_laino · Answer

the missing statement is:
$$\Large  m\angle ACE = m\angle ACD + m\angle DCE$$
for angle addition postulate

anonymous · Answer

omg okay thanks so much, now i have to explain why we needed this step

anonymous · Answer

cam i say because DBC=Eac?

anonymous · Answer

so without it we wouldn't be able to prove this?

michele_laino · Answer

no, since the condition DBC= EAC is necessary nevertheless it is not suffice

anonymous · Answer

Oh, okay

michele_laino · Answer

my condition is necessary since we have:
|dw:1433462306474:dw|
then the two triangles are congruent each other