document.write( "Question 246187: Please help me solve this word problem.\r
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document.write( "The perimeter of a rectangle is 210ft. The length is 15ft. less than twice the width. What is the length and the width? \r
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document.write( "I have tried dividing 210 by 6, getting 35 for each width, and 70 for each length. Then I added the widths (35+35), to get 70. I subtracted 15 from 70 and got a sum of 55 and divided that by 2 getting(27.5). I then added 15 to both of my lengths (15+70+70), and divided that by 2 getting 77.5. Am I correct that the length is 77.5ft., and the width is 27.5ft.? \n" );
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Algebra.Com's Answer #179831 by oberobic(2304) ![]() You can put this solution on YOUR website! Perimeter = 2L + 2W, where L = length and W = width. \n" ); document.write( "We are told \n" ); document.write( "L is 15 less than 2W, so we can interpret this as \n" ); document.write( "L + 15 = 2W ...(the length + 15 = 2W)...or equivalently, \n" ); document.write( "L = 2W -15 \n" ); document.write( ". \n" ); document.write( "We are told P = 210. \n" ); document.write( ". \n" ); document.write( "Substituting we have: \n" ); document.write( ". \n" ); document.write( "210 = 2L + 2W \n" ); document.write( "210 = 2(2W-15) + 2W \n" ); document.write( "210 = 4W - 30 + 2W \n" ); document.write( "210 = 6W - 30 \n" ); document.write( "240 = 6W \n" ); document.write( "6W = 240 \n" ); document.write( "W = 40 \n" ); document.write( ". \n" ); document.write( "L = 2W - 15 = 80 - 15 = 65 \n" ); document.write( ". \n" ); document.write( "So the dimensions are: \n" ); document.write( "L = 65 \n" ); document.write( "W = 40 \n" ); document.write( ". \n" ); document.write( "By the way we solved it, we know L is 15 less than 2 times width. \n" ); document.write( "But we can check the perimeter. \n" ); document.write( "2L = 2(65) = 130 \n" ); document.write( "2W = 2(40) = 80 \n" ); document.write( "2L + 2W = 210 \n" ); document.write( "Checks. \n" ); document.write( " |