document.write( "Question 117900: Geometry. The length of a rectangle is 1 cm longer than its width. If the diagonal
\n" ); document.write( "of the rectangle is 4 cm, what are the dimensions (the length and the width) of the rectangle?
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Algebra.Com's Answer #85930 by MathLover1(20850)\"\" \"About 
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\n" ); document.write( "If the length \"L\" of a rectangle is \"1+cm\" longer than its width \"W\", then we have\r
\n" ); document.write( "\n" ); document.write( "\"L+=+W+%2B+1cm\"
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\n" ); document.write( "the diagonal \"d+=+4cm\"\r
\n" ); document.write( "\n" ); document.write( "since the diagonal cutting a rectangle into two right triangles, we will use Pythagoras Theorem to find what the length and the width are\r
\n" ); document.write( "\n" ); document.write( "\"d%5E2+=+L%5E2+%2B+W%5E2\"….substitute \"d\" and \"L\"\r
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\n" ); document.write( "\"%284cm%29%5E2+=+%28W+%2B+1cm%29+%5E2+%2B+W%5E2\"\r
\n" ); document.write( "\n" ); document.write( "\"16cm%5E2+=+W%5E2+%2B+2Wcm+%2B+1cm%5E2%2B+W%5E2\"
\n" ); document.write( "\"16cm%5E2+=+2W%5E2+%2B+2Wcm+%2B+1cm%5E2\"
\n" ); document.write( "\"16cm%5E2+%96+%281cm%29%5E2=+2W%5E2+%2B+2Wcm+\"
\n" ); document.write( "\"15cm%5E2+=+2W%5E2+%2B+2Wcm+\"
\n" ); document.write( "\"+0=2W%5E2+%2B+2Wcm+%96+15cm%5E2+\"….now we can use quadratic formula to solve for \"W\"
\n" ); document.write( "Since \"a=2\", \"b=2\", and \"c+=+-15\", we will have:\r
\n" ); document.write( "\n" ); document.write( "\"W%5B1%2C2%5D=%28-2+%2B-+sqrt+%282%5E2+-4%2A2%2A%28-15%29+%29%29+%2F+%282%2A2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"W%5B1%2C2%5D=%28-2+%2B-+sqrt+%284+%2B+120+%29%29+%2F+4\"\r
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\n" ); document.write( "\n" ); document.write( "\"W%5B1%2C2%5D=%28-2+%2B-+sqrt+%28124+%29%29+%2F+4\"\r
\n" ); document.write( "\n" ); document.write( "\"W%5B1%2C2%5D=%28-2+%2B-+11.14+%29+%2F+4\"\r
\n" ); document.write( "\n" ); document.write( "Since we are looking for width, we need only positive solution:\r
\n" ); document.write( "\n" ); document.write( "\"W%5B1%5D=%28-2+%2B+11.14+%29+%2F+4\"\r
\n" ); document.write( "\n" ); document.write( "\"W%5B1%5D=%28+9.14+%29+%2F+4\"\r
\n" ); document.write( "\n" ); document.write( "\"W%5B1%5D+=+%282.285%29cm\"
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\n" ); document.write( "Then\r
\n" ); document.write( "\n" ); document.write( "\"L+=+W+%2B+%281cm%29\"\r
\n" ); document.write( "\n" ); document.write( "\"L+=+%282.285%29cm+%2B+%281cm%29\"\r
\n" ); document.write( "\n" ); document.write( "\"L+=+%283.285%29cm+\"\r
\n" ); document.write( "\n" ); document.write( "Check:\r
\n" ); document.write( "\n" ); document.write( "\"d%5E2+=+L%5E2+%2B+W%5E2\"….\r
\n" ); document.write( "\n" ); document.write( "\"d=+sqrt%28L%5E2+%2B+W%5E2%29\"….
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\n" ); document.write( "\"4+=+sqrt%28%283.285%29%5E2+%2B+%28%282.285%29%5E2%29%29\"….\r
\n" ); document.write( "\n" ); document.write( "\"4+=+sqrt%28+10.79+%2B+5.22%29\"….\r
\n" ); document.write( "\n" ); document.write( "\"4+=+sqrt%28+16%29\"….\r
\n" ); document.write( "\n" ); document.write( "\"4+=+4\"….\r
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