Five-Sided Lot Acreage Calculator
With this calculator you can calculate the size of a parcel of land in acres
or hectares. Start by using your mouse to drag the points at the corners of the
shape shown above. The numbers indicated on the sides represent the length of
those respective sides of the property.
If you set the sides to their lengths in feet, then use the value in the Acres
box. If you set the sides to their lengths in meters, then use the value in
the Hectares box. Then you also have the Square Units value.
In practical application it's difficult to measure the area of a property with
more than four sides. You need a long tape measure and some way to divide the
lot into regular shapes, like rectangles and triangles. Since this usually
requires measurements across the center of the lot, and since there is usually
a structure blocking the center, this can be difficult. Calculations would be
easier if you could measure the angles of the corners of a lot, but that's not
easy either. I would say your best bet is to get a piece of graph paper and
divide the lot up into triangles the best you can, and then use
area = 1/2 x base x height to calculate the area of each triangle.
This application divides the five-sided polygon into three triangles. The areas
of the triangles are calculated using the formula shown below and found at
mathopenref.com/coordtrianglearea.html.
[Ax(By-Cy)+Bx(Cy-Ay)+Cx(Ay-By)]/2
The areas of the triangles are then added together to determine the area of
the five-sided polygon.
Since it would be extremely time consuming to thoroughly test this application,
I have NOT thoroughly tested it. Before using this calculator, read
My Web Site User Agreement.
When the shape of the five-sided polygon is adjusted to a certain point (concave
rather than convex), the area of a triangle needs to be subtracted from the area
of the polygon, rather than added. When one of the points of the polygon is moved
across one of the sides of the shape, then you actually end up with two or three shapes,
not just a single polygon. It is unlikey that this calculator will give an
accurate result if you move one of the points of the polygon across one of the
sides of the shape.
It would be extremely time consuming to thoroughly test this application with
every possible shape that the user can create, therefore use it at your own risk.
I make no claims as to its accuracy and take no responsibility for its use. Use
it at your own risk. All I can say is, it appears to work, and having something
is probably better than having nothing.
You can usually estimate the size of a lot to see the results of this calculator
are reasonable. I would really appreciate it if someone would take the time to test
the application and inform me (through the contact form on this website) as to your
results. In fact I would appreciate anyone's comments in regard to this application.
please contact me using the
Contact form
on this Web site.
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