document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=171389>Question 171389</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A rectangular swimming pool has length 30 m by 20 m. There is a deck of uniform width surrounding the pool. The area of the pool is the same as the area of the deck. Write a quadratic equation to model this situation and use it to determine the width of the deck. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #126553 by </B><A HREF=/tutors/aboutme.mpl?userid=midwood_trail><B>midwood_trail(310)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=midwood_trail><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=126553\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A rectangular swimming pool has length 30 m by 20 m. There is a deck of uniform width surrounding the pool. The area of the pool is the same as the area of the deck. Write a quadratic equation to model this situation and use it to determine the width of the deck.\r<BR>\n" );
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document.write( "The area of the pool is 30m times 20m = 600m^2.\r<BR>\n" );
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document.write( "Let x = uniform width around the pool.\r<BR>\n" );
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document.write( "Width of bigger rectangle around the pool or deck = 2x + 20.\r<BR>\n" );
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document.write( "Length of bigger rectangle around the pool or deck = 2x + 30.\r<BR>\n" );
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document.write( "The question tells us that the area of the deck = the area of the pool.\r<BR>\n" );
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document.write( "We know the area of the pool = 600m^2.\r<BR>\n" );
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document.write( "So, your equation is:\r<BR>\n" );
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document.write( "(2x + 30) (2x + 20) = 600m^2\r<BR>\n" );
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document.write( "1.Solve for x.\r<BR>\n" );
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document.write( "2.Plug your value for x in the width of the bigger rectangle given above, which is the width of the deck.\r<BR>\n" );
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document.write( "Can you take it from here?\r<BR>\n" );
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document.write( "I received your reply.\r<BR>\n" );
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document.write( "The answer for x has to be positive.\r<BR>\n" );
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document.write( "I got two answers for x:\r<BR>\n" );
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document.write( "x = 5 and x = -30.\r<BR>\n" );
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document.write( "You did not use FOIL correctly.  That is why your answers for x were 3-digit numbers.  \r<BR>\n" );
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document.write( "Now, we totally reject x = -30 because distance is always positive.\r<BR>\n" );
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document.write( "For example. if you live 150 feet from the store, you would say:\r<BR>\n" );
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document.write( "I live 150 feet from the store.\r<BR>\n" );
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document.write( "You would not say: I live -150 feet from the store.\r<BR>\n" );
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document.write( "Now the width for the deck is: 2x + 20 and the length of the deck is\r<BR>\n" );
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document.write( "2x + 30.\r<BR>\n" );
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document.write( "To find the the right answers, replace x with 5 in BOTH expressions and you will find the right measurements for the deck of the pool.\r<BR>\n" );
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document.write( "Is this clear?\r<BR>\n" );
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document.write( " </SPAN>\n" );
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