A Hexagonal Geometric Sum (visual proof without words)

From a channel Lumen includes in full: Mathematical Visual Proofs is Tom Edgar's channel of animated proofs without words (sums, inequalities, geometry, combinatorics), each sourced from a published visual proof.

A 2-minute video from Mathematical Visual Proofs's catalogue; the title names its topic.

Video by Mathematical Visual Proofs, played through YouTube's embedded player.