What is the area of the composite figure?

The correct answer is 34 sq. units.

Explanation:
This is a trapezoid with a rectangle cut from the bottom. The two bases of the trapezoid are 10 and 6, and the height is 5.

The formula for the area of a trapezoid is A=1/2(B+b)(h), where B is the big base, b is the small base, and h is the height. Using our information, we have A=1/2(10+6)(5) = 1/2(16)(5) = 1/2(80) = 40.

The rectangle that is cut out has dimensions of 3 by 2; the area of it would be 3*2=6. Taking this out of the trapezoid, we have an area of 40-6=34 sq. units.

You seem to have a trapezoid with bases 10 and 6 and height 5, with a 2 by 3 rectangle cut out of it.

The area of a trapezoid is given by
  A = (1/2)(b1 +b2)h
  A = (1/2)(10 + 6)5 = 40

The area of the missing rectangle is the product of its length and width
  A = 3*2 = 6

Then the shaded area is the difference of these
  composite area = 40 - 6 = 34 square units

He gained 60,900 dollars for that land