The volume of water in a rectangular swimming pool can be modeled by the polynomial 2x^3-9x^2+7x+6. If the depth of the pool is given by the polynomial 2x + 1, what polynomials express the length and width of the pool?

Respuesta :

The area of the base is given by
[tex]B=\frac{V}{h}[/tex]

We are given
[tex]V=2x^{3}-9x^{2}+7x+6[/tex] and [tex]h=2x+1[/tex]
[tex]\rightarrow B=\frac{2x^{3}-9x^{2}+7x+6}{2x+1}[/tex]
which we can solve with long division:
                     x^2 -5x+6
2x+1 | 2x^3-9x^2+7x+6
           2x^3+ x^2
          --------------------------
                -10x^2+7x
                -10x^2-5x
                 --------------------
                          12x+6
                          12x+6
                         -----------
                                  0

So [tex]B=x^{2}-5x+6[/tex]
which can be factored as
[tex](x-2)(x-3)[/tex]

So the length and width are [tex]x-2[/tex] and [tex]x-3[/tex].