area of a parking lot: One campus of Houston community college has plans to construct a rectangular parking lot on land bordered on one side by a highway. there are 640 feet of fencing available to fence the sides. let x represent the length of each off the two parallel sides of fencing.

a)Draw the illustration of the problem
b) express the length of the remaining side to be fenced in terms of x.
c)what are the restrictions of x?
d)determine the values of x that will give an area between 30,000 and 40,000 feet squared.
e)what dimensions will give a maximum area, and what will this area be?
f)determine a function A that represents the area of the parking lot in terms of x?

2 answers

Just take it step by step.
total fence: 640
two parallel sides: 2x

b) remaining side: 640-2x
c) obviously 640-2x>0 ==> x < 320
d) 30000 < x(640-2x) < 40000
56 < x < 85 approx
e) max area approx 51000 at x=160
f) a = x(640-2x)
thanks! i have one more that i posted about the path of a frogs leap. I can't figure it out