The bases of an isosceles trapezoid are represented by 4x and 2x.. the height of the trapezoid is represented by (x − 6). which polynomial expression best represents the area of the trapezoid?

The formula for solving the area of a trapezoid is shown below:
Area = ((a+b)/2 ) * h
where "a" and "b" for the base and "h" for the height
 a = 4x
b = 2x
c = (x-6) 

The solution for the polynomial expression is shown below:
Area = (4x + 2x)/2  * (x-6)
Area = 6x/2 * (X-6)
Area = 3X * (X-6)
Area = 3X²  - 18X

The answer is 3X² - 18X.