Answer:
A(x) = -2X² + 600X
Explanation:
Area = X · Y
Perimeter = 2X + Y = 600
Y = 600 - 2X
A(x) = X · (600 - 2X) = 600X - 2X²
A(x) = -2X² + 600X
if you want to maximize area:
A'(x) = -4X + 600 = 0
600 = 4X
X = 150
Y = 600 - (2 · 150) = 600 - 300 = 300
Area = 150 · 300 = 45,000 ft²