What is the area of a hexagon with 4 cm long sides?
Obviously, this question is about a regular 6-sided polygon. That means that all sides are equal (4 cm long each) and all inside angles equal to each other. That's what regular means, without this word the problem is not fully specified.
Every regular polygon has a center of rotational symmetry. If we rotate it around this center by
In case of a regular hexagon
In an equilateral triangle with a side
Area of such a triangle is
From this the area of the regular hexagon with a side