let the single side be y ft, the two equal sides be x
2x + y = 300
y = 300-2x
area = xy = x(300-x)
= -2x^2 + 300x
you want the vertex of this downwards parabola
the x of the vertex is -b/(2a) = -300/-4 = 75
y = 300-150 = 150
max area = xy = 75(150) = 11250 ft^2
You have 300 feet of fence. You need to build a garden, where 3 walls are fence and the 4th wall is your house. What is the maximum area of the garden you can make with 300 feet of fence?
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