Complete the proof.

Given: Line `stackrelharr(AB)` intersects line `stackrelharr(DC)` at point `E` ; `/_AEB` and `/_DEC` are straight angles.

Prove: `/_AEC~=/_DEB`

Complete the proof Given Line stackrelharrAB intersects line stackrelharrDC at point E AEB and DEC are straight angles Prove AECDEB class=