document.write( "Question 1150605: A 8 yard by 10 yard swimming pool is surrounded by a deck of uniform width.the area of the deck is 72yd squared . Find the width of the deck \n" ); document.write( "

Algebra.Com's Answer #771988 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "The area of 72 square yards is the difference of the area of the larger rectangle and the pool's area.\r\n" );
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document.write( "Let w be the uniform width of the deck.\r\n" );
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document.write( "Then the dimensions of the larger rectangle are  (8+2w) yards and (10+2w) yards, \r\n" );
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document.write( "and its area is  (8+2w)*(10+2w).\r\n" );
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document.write( "Thus you have this equation\r\n" );
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document.write( "    (8+2w)*(10+2w) = 8*10 + 72.\r\n" );
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document.write( "Simplify it\r\n" );
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document.write( "    80 + 20w + 16w + 4w^2 = 80 + 72\r\n" );
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document.write( "    4w^2 + 36w - 72 = 0\r\n" );
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document.write( "     w^2 +  9w - 18 = 0\r\n" );
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document.write( "      =  = .\r\n" );
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document.write( "Only positive root makes sense  w =  = 1.685  yards.    ANSWER\r\n" );
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document.write( "CHECK.  (8+2*1.685)*(10+2*1.685) - 8*10 = 72.0169  very close to 72 square yards.   ! Correct !\r\n" );
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\n" ); document.write( "\n" ); document.write( "Closely related lessons to it are the lessons\r
\n" ); document.write( "\n" ); document.write( "    - Problems on the area and the dimensions of a rectangle surrounded by a strip\r
\n" ); document.write( "\n" ); document.write( "    - Cynthia Besch wants to buy a rug for a room \r
\n" ); document.write( "\n" ); document.write( "    - Problems on a circular pool and a walkway around it\r
\n" ); document.write( "\n" ); document.write( "in this site.\r
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\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-I in this site\r
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lesson is the part of this online textbook under the topic
\n" ); document.write( "\"Dimensions and the area of rectangles and circles and their elements\".\r
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\n" ); document.write( "\n" ); document.write( "Save the link to this online textbook together with its description\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-I
\n" ); document.write( "https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson\r
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\n" ); document.write( "\n" ); document.write( "to your archive and use it when it is needed.\r
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