Area and Perimeter?
The square feet is confusing me the most; I don’t know how to convert it to regular feet.
Favorite Answer
If x ft. is the length of each of the two sides of the fence perpendicular to the wall, then the length of the third side is:
240 – 2x ft.
The area A (sq. ft) is the length multiplied by the width:
A = x(240 – 2x)
Therefore:
x(240 – 2x) = 5500
Extract the common factor of 2 on the LHS:
2x(120 – x) = 5500
x(120 – x) = 2750
Multiply out and subtract 2750:
120x – x^2 – 2750 = 0
x^2 – 120x + 2750 = 0
x = ( 120 +/- sqrt(120^2 – 4*2750) ) / 2
= 60 +/- 29.15
x = 89.15 or 30.85 ft.
P = y + x + x
240 = y + 2x
Area formula
Area = w * L
Area = y * x
solve y:
y = 240 – 2x
Area = x (240 – 2x)
Area = -2x^2 + 240x
we want the area to be 5500 ft^2
5500 = -2x^2 + 240x
0 = -2x^2 + 240x – 5500
use quadratic formula and you’ll get:
x = 30.845ft or 89.154ft
