I have been given this question for my maths class, and would appreciate some help. This is the full question.

A different pool at the complex, is constructed within a hole which has a volume equal to 12x^3 + 20x^2 - 81x - 14m^3, and the depth represented by (x - 2) m.

Find the width and length of the hole in terms of x.

Let me explain a bit more, the current assignment is you work for a pool complex and have to find the measurments for the holes required to put in a hole. I need to find out the length and width which I have been given the depth and the equation to do. I have learnt nothing about cubics before and have done as little as quadratics. If you need more info feel free to ask.

Thanks in advance