document.write( "Question 1171583: The length of a rectangle is 7 less than the width. The area is 30. Find the dimensions, then find the perimeter. \n" ); document.write( "

Algebra.Com's Answer #796467 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "ANSWER.  The dimensions are  3 units (the length) and 10 units (the width).  The perimeter is  3 + 10 + 3 + 10 = 26 units.\r\n" );
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document.write( "Solution\r\n" );
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document.write( "    x*(x+7) = 30\r\n" );
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document.write( "    x^2 + 7x - 30 = 0\r\n" );
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document.write( "    (x-3)*(x+10)  = 0\r\n" );
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document.write( "The roots are 3 and -10, and only positive root works.\r\n" );
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document.write( "It is 3 units, the width.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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\n" ); document.write( "\n" ); document.write( "The solution can be guessed mentally in 2 seconds.\r
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\n" ); document.write( "\n" ); document.write( "If you want to see other similar solved problems with detailed explanations, look into the lesson\r
\n" ); document.write( "\n" ); document.write( " - Problems on the area and the dimensions of a rectangle surrounded by a strip\r
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