Question

question

Answer 1

I'm sure there are several ways in which you could solve this problem.
Note that if the width is x+15, you could divide that into the box volume x^3+5x^2-57x-189 and thereby obtain an expression for the length times the height. Perhaps that quotient could be factored further.

Note that you are told that the width is 15, but also that the width is x+3. Please solve this for x. You're not done yet, however: You still need to find the length and depth.

Answer 2

ok, i think (b)

Answer 3

@mathmale

Answer 4

sorry, @mango45, but I decided long ago that I do not deal in a, b, c or d answers without an explanation of how you chose your answer. I did suggest two specific things you could do:

1) divide x+3 into the given polynomial, and
2) solve x+3=15 inches.

Answer 5

either do those two things now, or explain how you happened to "think" b.