The length of the rectangle is defined by [tex](x-1)\cdot \left(x-\frac{1}{3} \right)[/tex].
Geometrically speaking, the rectangle area is equal to the product of its base and its length. According to the statement the area is represented by a third order polynomial and width by a first order polynomial and, thus, length must be a second order polynomial.
By factor the polynomial we get the following roots:
[tex]A = 3\cdot x^{3}+14\cdot x^{2}-23\cdot x + 6[/tex]
[tex]A = (x+6)\cdot (x-1)\cdot \left(x-\frac{1}{3} \right)[/tex]
Then, the length of the rectangle is defined by [tex](x-1)\cdot \left(x-\frac{1}{3} \right)[/tex].
To learn more on rectangles, we kindly invite to check this verified question: https://brainly.com/question/10046743