math 099
posted by Anonymous .
a rancher wants to use 300 feet of fencing to enclose a rectangular area of 4400 square feet. what dimensions should the rectangle have?

length = x
width = y
x+y = 150 , y = 150x
xy = 4400
x(150x) = 4400
expanding and simplifying...
x^2  150x + 4400 = 0
(x110)(x40) = 0
x = 110 or x=40
if x=110, then y = 40
if x = 40, then y = 110
the dimenstions should be 110 ft by 40 ft
check: 2(110+40) = 300
(110)(40) = 4400