document.write( "Question 708486: How do I solve for the sides of a rectangle when given only the perimeter (40 feet) and the square feet (90 sq. ft)? Thank you! \n" ); document.write( "

Algebra.Com's Answer #436116 by solver91311(24713) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "Let

represent the width and

represent the length.\r
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\n" ); document.write( "\n" ); document.write( "The perimeter of a rectangle is given by

\r
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\n" ); document.write( "\n" ); document.write( "So we know that

which is to say

, or, better for our purposes,

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\n" ); document.write( "\n" ); document.write( "The area of a rectangle is the length times the width, so:\r
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\r
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\n" ); document.write( "\n" ); document.write( "Putting the quadratic into standard form:\r
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\r
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\n" ); document.write( "\n" ); document.write( "Solve the quadratic for

. Discard the value that produces a negative result when you calculate

. Note: This quadratic DOES NOT factor over the rationals. Use the quadratic formula, but leave your answer in simplest radical form.\r
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\n" ); document.write( "\n" ); document.write( "John
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\n" ); document.write( "Egw to Beta kai to Sigma
\n" ); document.write( "My calculator said it, I believe it, that settles it
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$\"The$

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