document.write( "Question 31294: please help me with this question i dont understand it at all. find the dimensions of a rectangle a with the greatest area whose perimeter is 30 feet.thank you so much. \n" ); document.write( "
Algebra.Com's Answer #17962 by josmiceli(19441)\"\" \"About 
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The perimeter is 30 feet
\n" ); document.write( "Call the perimeter p
\n" ); document.write( "p = 30
\n" ); document.write( "I want to maximize the area
\n" ); document.write( "What if the rectangle is a square?
\n" ); document.write( "Then the 4 sides are:
\n" ); document.write( "7.5, 7.5, 7.5, 7.5
\n" ); document.write( "The sides add up to 30, so p = 30 as it should
\n" ); document.write( "What's the area? Call it a
\n" ); document.write( "a = 7.5 * 7.5 = 56.25
\n" ); document.write( "Suppose I change the square just a little
\n" ); document.write( "Subtract .5 from two opposite sides and add .5
\n" ); document.write( "to the other two opposite sides
\n" ); document.write( "Now I have
\n" ); document.write( "7, 7, 8, 8
\n" ); document.write( "They add up to 30 as they should
\n" ); document.write( "a = 7 * 8 = 56
\n" ); document.write( "If I try other numbers for sides that add up to 30
\n" ); document.write( "6, 6, 9, 9
\n" ); document.write( "a = 6 * 9 = 54
\n" ); document.write( "The longer and narrower I make the rectangle, the area
\n" ); document.write( "keeps getting smaller, so the square with a = 56.25
\n" ); document.write( "is the largest area I can get with perimeter = 30
\n" ); document.write( "(or any size perimeter, for that matter) \n" ); document.write( "
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