1. Let x be a length of square side, then the square perimeter is 4x (you need to cut 4x from 16 in. to make a square with side x in.). Then 16-4x is remained length of wire and you have to make form this piece a rectangle with sides one of which is twice bigger than another. If y is length of the smaller side, then 2y is length of the bigger side and rectangle perimeter is y+2y+y+2y=6y. You have 16-4x in. of wire left, so 6y=16-4x and 
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3. Find the derivative of the function A(x):
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4. Solve the equation A'(x)=0:
5. Since you have
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Answer: <span>the width of the rectangle is
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2.
3. Find the derivative of the function A(x):
4. Solve the equation A'(x)=0:
5. Since
Answer: <span>the width of the rectangle is