Diagonal
Initial Definition

A diagonal is a line segment that joins two non-adjacent vertices in a polygon (or polyhedron).


Diagonal examples (regular pentagon)

Diagonal example (polyhedron)

More

In a convex polygon, all diagonals will occur in the interior of the polygon, as illustrated the the example below left.


Diagonals (convex and concave polygon) examples

In a concave polygon, NOT all diagonals (or all of a diagonal) will occur in the interior of the polygon, as illustrated the the example above right.


Demonstration
Image only

Instructions text as in global.js

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