document.write( "Question 1114953: The area of a playground is 168 𝑦𝑑2.
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Algebra.Com's Answer #732424 by ikleyn(52777) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "Let x be the number (now unknown) which is exactly half way between the width and the length of the playground.\r\n" );
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document.write( "Then, as you understand,  the length = (x+1)  and  the width = (x-1).\r\n" );
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document.write( "The area = 168 = length*width = (x+1)*(x-1).\r\n" );
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document.write( "Thus (x+1)*(x-1) = 168,  which implies   = 168,  i.e.   = 168+1 = 169.\r\n" );
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document.write( "Hence, x =  = 13.\r\n" );
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document.write( "Then the length = 13+1 = 14  and the width = 13-1 = 12.\r\n" );
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\n" ); document.write( "\n" ); document.write( "To see many other problems solved by same (quite unexpected) method, look into the lesson\r
\n" ); document.write( "\n" ); document.write( " - HOW TO solve the problem on quadratic equation mentally and avoid boring calculations \r
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document.write( "The method above you may find in some recreational books.\r\n" );
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document.write( "Sometimes in math circles the teachers explain it to students.\r\n" );
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document.write( "But in the school Math, the standard method of solution is to reduce the problem to a quadratic equation\r\n" );
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document.write( "w*(w+2) = 168\r\n" );
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document.write( "and then solve it using the quadratic formula or factoring.\r\n" );
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document.write( "When you do it by factoring, you need to guess two numbers with the difference of 2 and the product of 168.\r\n" );
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document.write( "You can do it by sorting through different factors of the number 168, as the tutor @shin123 explained it in his post.\r\n" );
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\n" ); document.write( "So, it was as if you visited a Math circle today . . . \r
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