There is no short cut. Measure the length of each side and sum the lengths together.
You may be lucky and the irregular polygon may have sides of the same length but different angles - and that will reduce the effort required..
Different polygons have different relationships between perimeter and area. For example, if we assume regular polygons, an equilateral triangle and a square have different perimeters for the same area. If you allow irregular polygons, the variety is even bigger.
There is insufficient information to answer the question. For a given area, the perimeter depends upon the shape. For a given area, the circle will have the smallest perimeter. For polygons, regular polygons will have a smaller perimeter than an irregular one of the same area. Also, for regular polygons, the greater the number of sides, the smaller the perimeter.
There is no general formula for all irregular polygons.
Irregular polygons.
by subtracting
You add up the length of all the sides.
To find the perimeter of polygon efgh, you need the ratio of similarity between polygons abcd and efgh, as well as the perimeter of polygon abcd. Once you have the perimeter of abcd, multiply it by the ratio to obtain the perimeter of efgh. If the ratio is not provided, it cannot be determined.
It cannot be any regular polygon, not a rectangle. But it could be a triangle or irregular polygons with 4 or more sides.It cannot be any regular polygon, not a rectangle. But it could be a triangle or irregular polygons with 4 or more sides.It cannot be any regular polygon, not a rectangle. But it could be a triangle or irregular polygons with 4 or more sides.It cannot be any regular polygon, not a rectangle. But it could be a triangle or irregular polygons with 4 or more sides.
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irregular polygons are just polygons that do not have equal angles and side so a scaling and isosceles triangles are 2 and trapezoid is another.
Regular polygons have all sides equal in length but an irregular polygon does not have all sides equal.
Regular polygons have all equal length sides and irregular polygons do not.