### Theory:

A polygon is a closed shape that has at least three sides. Triangles, quadrilaterals, rectangles and squares are all types of polygons.
A polygon can be of any shape and can have any number of sides. There is no specific formula for calculating the area of a polygon. The best way is to split the polygon into known shapes whose area can be calculated individually.
Example:

In this figure, the area of polygon $$ABCDE$$ is spilt in the form of two diagonals, $$AC$$ and $$AD$$. It divides the polygon into three parts.

Thus, the area of polygon $$ABCDE =$$ Area of $$△ ABC$$ $$+$$ Area of $$△ ACD$$ $$+$$ Area of $$△ AED$$.