document.write( "Question 1204421: Cynthia Besch wants to buy a rug for a room that is 27ft wide and 35ft long. She wants to leave a uniform strip of floor around the rug. She can afford to buy 609 square feet of carpeting. What dimensions should the rug​ have? \n" ); document.write( "
Algebra.Com's Answer #840651 by math_tutor2020(3817)![]() ![]() ![]() You can put this solution on YOUR website! \n" ); document.write( "A question like this has been asked before.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Review this link to see an example how to solve. \n" ); document.write( "https://www.algebra.com/algebra/homework/quadratic/Quadratic_Equations.faq.question.1197474.html\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "If you are still stuck, then read on.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "--------------------------------------------------------------------------\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Draw out a diagram as indicated in the link above.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "There will be a large rectangle that is 27 feet by 35 feet. \n" ); document.write( "This represents the dimensions of the room.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Inside that larger rectangle will be a smaller rectangle with dimensions (27-2x) feet by (35-2x) feet. \n" ); document.write( "x represents the width of the uniform strip. \n" ); document.write( "This is the buffer gap between the edge of the rug to the edge of the wall.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "The area of the smaller rectangle is (27-2x)(35-2x). \n" ); document.write( "Set this equal to 609 because this is the amount of carpet she can buy.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "(27-2x)(35-2x) = 609 \n" ); document.write( "27(35-2x)-2x(35-2x) = 609 \n" ); document.write( "945-54x-70x+4x^2 = 609 \n" ); document.write( "945-54x-70x+4x^2 - 609 = 0 \n" ); document.write( "4x^2 - 124x + 336 = 0 \n" ); document.write( "4(x^2 - 31x + 84) = 0 \n" ); document.write( "x^2 - 31x + 84 = 0\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "We could factor, but I think the quadratic formula is the most efficient pathway. \n" ); document.write( "This is because we don't have to worry about guess-and-check.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Plug a = 1, b = -31, c = 84 into the quadratic formula below. \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "If x = 28, then 27-2x = 27-2*28 = -29, which is not valid. \n" ); document.write( "The side length must be positive.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "If x = 3, then, \n" ); document.write( "27-2x = 27-2*3 = 21 \n" ); document.write( "and \n" ); document.write( "35-2x = 35-2*3 = 29 \n" ); document.write( "Both results are positive. \n" ); document.write( "Therefore x = 3 is valid and practical. \n" ); document.write( "A gap of 3 feet produces a rug that is 21 feet by 29 feet.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "As a check, 21*29 = 609, and we have confirmed the answer is correct.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "-------------------------------------------------------------------------- \n" ); document.write( "--------------------------------------------------------------------------\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Answer: The rug should be 21 feet by 29 feet. \n" ); document.write( " \n" ); document.write( " |