At least they admitted this is algebra not geometry. You'll get the same question next year but they'll call it geometry.
The area is the product of the sides:
[tex]A=(x-6)(3x^2-4x+6)[/tex]
We just distribute and collect terms:
[tex]A=x(3x^2-4x+6) - 6(3x^2-4x+6) [/tex]
[tex]A=3x^3-4x^2+6x - 18x^2 +24x -36[/tex]
[tex]A=3x^3- 22x^2+30x-36[/tex]
Answer: 3rd choice
