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1. Δ ABC ~ Δ DBE
2. Side Angle Side similarity theorem
What is Side Angle Side similarity theorem
The SAS similarity theorem states if an angle of one triangle is congruent to an angle of another triangle, and the included sides (the sides between the angles) are proportional, then the two triangles are similar.
The parts used in the proof includes
Side: AB ~ DB
Angle: ∠ B ≅ ∠ B
Side: BC ~ BE
The sides are proportional while the angles are congruent