# Math Help - Factoring polynomial

1. ## Factoring polynomial

The volume of a rectangular box with a square base is 175x^2+210x+63. If the height is 7 units, what is (show all work) a)the dimensions of the base b)the perimeter of the base
Thank you!

2. Originally Posted by johett
The volume of a rectangular box with a square base is 175x^2+210x+63. If the height is 7 units, what is (show all work) a)the dimensions of the base b)the perimeter of the base
Thank you!
what does x represent here?

3. it doesn't say...that's all that has been given from the question

4. Since the base is square, then we can set $7y^{2}=175x^{2}+210x+63$ and solve for y. Where y is the width(and length) of the base.

$\frac{175x^{2}+210x+63}{7}=25x^{2}+30x+9=(5x+3)^{2 }$

$y=\sqrt{(5x+3)^{2}}=|5x+3|$