# Math Help - finding lengths and other from algebraic equations of shapes

1. ## finding lengths and other from algebraic equations of shapes

a few questions

question 2
rectangular shape

area of land is represented by: 2x^2 + 17xy +21y^2

give the possible expressions that represent the dimmensions, and
a fence will be planted around the shape, and it will be x meters from the pitch. Give the algebreic expression that reprsents the length of hte proposed fencing
question 3

a box has a voulme of 12x^3 - 16x^2 -5x+3, and the top has a surface area of 6x^2 -11x +3, give the height

an fyi: this is not homework, this is from a pratice sheet for the nationwide exam tomorrow.

2. ## Re: finding lengths and other from algebraic equations of shapes

I don't know what "from the pitch" means for this problem so I'll go to question three.

we know that the volume of a box (in other words a prism EDIT:// not necessarily square)

V = (Surface Area) * z. Hence z = V / (Surface Area)

$z= \frac{12x^3-16x^2-5x+3}{6x^2-11x+3}$