Answer: The area of land =108 m²
Explanation:
In the given piece of land is in the shape of a parallelogram.
Diagonals divide it into 2 equal parts.
So, area of parallelogram = 2 x (Area of triangle with sides 12m and 9 m and 15 m)
Heron's formula :
Area of triangle =
, where

Let a= 12 , b= 9 and c = 15

Area of triangle =


Then, area of parallelogram= 2 x 54 = 108 m²
Hence, the area of land =108 m²