James,

You need to know more than the lengths of the sides to find the area. Your comment "Weird triangular shape." is the key. You need a way to describe the shape. Look at this response we gave to a another question to see an example of weird shapes with obviously different areas and yet the same side lengths. The example has 5 sides but you can do something similar with 4 shapes. If you know the length of a diagonal or the measure of one of the angles you can use our four-sides lot area calculator to find the area. If not, but you have a drawing of the lot, send it to us and we will see if we can find the area.

Harley