AD*EC=AE*DB gives

AD/DB=AE/EC ADD 1 BOTH SIDES

AD/AB=AE/AC GIVES TRIANGLES ADE AND ABC SIMILAR TRIANGLES

POSSIBLE ONLY IS IF DE IS PARALLEL TO BC

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In triangle ABC, D and E are points on sides AB and AC respectively such that AD × EC = AE × DB. Prove that DE || BC?

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