Given:
The base of the given figure = 23.8 ft
Height of the parallelogram = 15 ft
To find the area of the shaded region.
Formula
where,
be the area of the shaded region
be the area of the parallelogram.
be the area of the triangular part.
- The area of triangle
where, b be the base and h be the height.
- The area of the parallelogram

- By Pythagoras theorem,

Now,
Putting, Base = 21, Hypotenuse = 23.8 we get,

or,

or,

Therefore,
Area of the parallelogram
sq ft = 357 sq ft
Area of the triangle
=
sq ft = 117.6 sq ft
So,
The area of the shaded part = (357-117.6) sq ft = 239.4 sq ft
Hence,
The area of the shaded part is 239.4 sq ft.