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Vera has

60 ft of fencing and wants to enclose a patio, using an existing wall for one side as shown. The area of the patio can be modeled by À(x) = 60x - 3x3, where x is in feet. Find the maximum area of the patio.

User Aley
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1 Answer

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The maximum area of the patio is 300 ft², option (A).

How to determine the maximum area of the fence

The given area function is A(x) = 60x - 3x²

the critical points,is gotten by taking the derivative of the area function and set it equal to zero:

A(x) = 60x - 3x²

A'(x) = 60 - 6x

Setting A'(x) = 0, we get:

60 - 6x = 0

x = 10.

The second derivative is

A''(x) = -6,

Since the second derivative is negative at x = 10, this confirms that x = 10 is a maximum.

substitute x = 10 into the original area function to find the maximum area:

A(10) = 60(10) - 3(10)²

= 600 - 300 = 300

Therefore, the maximum area of the patio is 300 ft², option (A).

Complete question

Vera has 60 ft of fencing and wants to enclose a patio, using an existing wall for-example-1
User Jorel Amthor
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