Question

the volume of a box is 45x^3 + 198x^2 + 189x. find expressions for the possible dimensions of the prism

Answer 1

Answer:

length, width, and height are (b+2), (b-2), (b+3)

Step-by-step explanation:

Doing what the problem statement tells you to do, you get ...

 (b^3 +3b^2) -(4b +12)

 = b^2(b +3) -4(b +3) . . . factor each pair of terms

 = (b^2 -4)(b +3) . . .  write as a product

 = (b -2)(b +2)(b +3) . . . use the factoring of the difference of squares

The three factors are (b-2) , (b+2) , and (b+3). We have no clue as to how to associate those with length, width, and height. We just know these are the dimensions of the box.