document.write( "Question 100153: Geomatry. The length of a rectangle is 1 cm longer than its width. If the diagnonal of the rectangle is 4cm what are the dimensions (the length and teh width) of the rectangle? \n" ); document.write( "
Algebra.Com's Answer #72975 by oberobic(2304)\"\" \"About 
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The statement that the \"length is 1 cm longer than the width\" means that we can define the length (l) = w + 1. Width (w) is simply = to w. So, the rectangle has sides of w, w+1, w, and w+1. The diagonal is known to be 4 cm (given).\r
\n" ); document.write( "\n" ); document.write( "Now we simply apply the Pythagorean formula. Let's call the diagonal d. That means \r
\n" ); document.write( "\n" ); document.write( "\"d%5E2+=+w%5E2+%2B+%28w%2B1%29%5E2\"\r
\n" ); document.write( "\n" ); document.write( "\"%28w%2B1%29%5E2+=+w%5E2+%2B+2w+%2B+1\"\r
\n" ); document.write( "\n" ); document.write( "Therefore, \"d%5E2+=+w%5E2+%2B+w%5E2+%2B+2w+%2B+1+=+2w%5E2+%2B+2w+%2B+1\"\r
\n" ); document.write( "\n" ); document.write( "Of course, \"d%5E2\" is the square of the diagonal, and we were told the diagonal was 4 cm, so \"d%5E2+=+16\".\r
\n" ); document.write( "\n" ); document.write( "Substituting what we know:\r
\n" ); document.write( "\n" ); document.write( "\"16+=+2w%5E2+%2B+2w+%2B+1\"\r
\n" ); document.write( "\n" ); document.write( "Subtracting 16 from both sides:\r
\n" ); document.write( "\n" ); document.write( "\"0+=+2w%5E2+%2B+2w+-+15\"\r
\n" ); document.write( "\n" ); document.write( "This does not factor easily, so you can use the quadratic equation to find w.\r
\n" ); document.write( "\n" ); document.write( "Quadratic formula: \"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"\r
\n" ); document.write( "\n" ); document.write( "Substituing, we have \"w+=+%28-2+%2B-+sqrt%28+2%5E2-4%2A2%2A%28-15%29+%29%29%2F%282%2A2%29+\"
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