document.write( "Question 4269: The perimeter of a rectangular floor is 42 feet, and the area is 108 square feet. Find the length of the floor. \n" ); document.write( "
Algebra.Com's Answer #1927 by Earlsdon(6294)\"\" \"About 
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Assign the variables: Let x = the length of the side of the square.
\n" ); document.write( "Then x+6 = the length of the diagonal. \r
\n" ); document.write( "\n" ); document.write( "Apply the Pythagorean theorem: c^2 = a^2 + b^2 c is the diagonal, a and b are the sides of the square.\r
\n" ); document.write( "\n" ); document.write( "(x+6)^2 = x^2 + x^2
\n" ); document.write( "x^2 + 12x + 36 = 2x^2 Subtract x^2 from both sides.
\n" ); document.write( "12x + 36 = x^2 Rewrite in standard quadratic form.\r
\n" ); document.write( "\n" ); document.write( "x^2 - 12x - 36 = 0 Solve the quadratic using the quadratic formula.\r
\n" ); document.write( "\n" ); document.write( "\"x=%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F2a%29\"
\n" ); document.write( "\"x=%2812%2B-sqrt%28-12%5E2-4%2A36%29%29%2F2%29\"\r
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