The volume of a rectangular prism is the product of the prism's dimension (i.e. length, width and height). The dimension of the rectangular prism are:
[tex]Length = 3x^2\\ Width = 2x - 1\\ Height = 3x + 4[/tex]
Given that:
[tex]Volume = (18x^4 + 15x^3 - 12x^2)[/tex]
First, we factor out [tex]3x^2[/tex]
[tex]Volume = 3x^2 \times (6x^2 + 5x - 4)[/tex]
Expand
[tex]Volume = 3x^2 \times (6x^2 + 8x-3x - 4)[/tex]
Factorize
[tex]Volume = 3x^2 \times (2x(3x + 4) -1(3x + 4))[/tex]
Factor out [tex]3x + 4[/tex]
[tex]Volume = 3x^2 \times ((2x -1) (3x + 4))[/tex]
Rewrite as:
[tex]Volume = 3x^2 \times (2x -1) \times (3x + 4)[/tex]
The volume of a rectangular prism is:
[tex]Volume = Length \times Width \times Height[/tex]
So; by comparison:
[tex]Length = 3x^2\\ Width = 2x - 1\\ Height = 3x + 4[/tex]
Read more about polynomials and volumes at:
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