Napkin on the plane
Source: St Petersburg Olympiad 2014, Grade 9, P5
October 27, 2017
combinatoricsgeometry
Problem Statement
On a cellular plane with a cell side equal to , arbitrarily napkin is thrown. It covers some nodes (the node lying on the border of a napkin, is also considered covered). What is the smallest number of lines (going not necessarily along grid lines) you can certainly cover all these nodes?