Sketch the parabola and rectangle to show that the height of the rectangle is y and half the width is x. The area we want can now be written as Area = 2xy=2x(8-x2). Take the derivative of the area to find dA/dx=16-8x2. Set that = 0 to find x=+/-2. Use the +2 and note the width = 2*2=4 and the height 8-22=4.
Stephen H.
tutor
The rectangle is 4 units wide and 4 units high
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11/22/21
Ryan R.
That is what I tried to enter and it is wrong? I got the same answer originally
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11/22/21
Stephen H.
tutor
Perhaps your answer key is wrong? It's a common problem
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11/22/21
Linda C.
I think dA/dx=16-6*x^2 therefore 0=dA/dx=16-6*x^2, and so on
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11/23/21
Ryan R.
I have tried to enter the 4 for the width and 4 for height considering what you gave me and it is wrong. Did you give me an example or was that the answer11/22/21