Question

Proof 1: Given two intersecting lines AB and CD at point E, prove that ∠AEC≅∠DEB. (You may NOT use the Vertical Angle Theorem.)




Statement
Reason

Answer 1

@Elsa213

Answer 2

so i think it in this way

angle AEC with angle CEB equal 180 degrees so let note angle AEC an E1 and angle CEB and E2
in a second way angle AED note E4 with angle DEB note E3 equal 180 degrees

but in an other way we can write that E1 +E4 = 180 degrees and that E2 +E3 = 180 degrees too

so there are

E1 + E2 = 180°
E3 +E4 = 180°

and

E1 + E4 = 180°
E2 + E3 = 180°

how you think what result from these above wrote ?

E2 need be equal E4 ?
and
E1 need be equal E3 ?

what is your opinion about these ?

hope helped understandably easy