Since AC∥DF, use alternate interior angles.
∠CBF=34° is formed between the transversal BF and AC. By alternate interior angles with the parallel line DF:
∠BFE=34°
Since △EBF is isosceles with BE≅BF, the base angles are equal:
∠BEF=∠BFE=34°
The angle ∠BED is supplementary to ∠BEF (they form a straight line along DE):
∠BED=180°−34°=146°
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