While doing the book "Probem Solving Strategies by Arthur Engel" I found this question:
"Can you draw a triangular map inside a pentagon, so that each vertex has an even degree?"
I know what degree of a vertex means, however I am not understanding what a triangular map means here? Also how do I solve this problem?
You can think of triangular map as of planar graph with all polygons that appear being topologically triangles (i.e. having 3 vertices and 3 edges).
This planar graph is not a triangular map because the face in the middle is quadrilateral. However, if you add diagonal to it, it becomes a triangular map.