document.write( "Question 47898: A rectangular enclosure must have an area of at least 900yd^2. If 200yd of fencing is to be used, and the width cannot exceed the length, within what limits must the width of the enclosure lie? \n" ); document.write( "
Algebra.Com's Answer #31697 by pizza(14)\"\" \"About 
You can put this solution on YOUR website!
Not so easy, this one.
\n" ); document.write( "I shall assume you know your algebra, and do not require much explanation.
\n" ); document.write( "Otherwise, you have to feedback and I will edit my solution.
\n" ); document.write( "First, let us set up the problem.\r
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\n" ); document.write( "\n" ); document.write( "Let w be the width and l be the length.
\n" ); document.write( "Then we have
\n" ); document.write( "(1): wl > 900
\n" ); document.write( "(2): 2w + 2l = 200\r
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\n" ); document.write( "\n" ); document.write( "From the second equation, we get l = 100 - w,
\n" ); document.write( "which put into the first equation gives w(100-w) > 900
\n" ); document.write( "which expands out to \"+0+%3E+w%5E2+-+100+%2B+900+\"
\n" ); document.write( "which factorises to be \"+0+%3E+%28w-10%29%28w-90%29+\"
\n" ); document.write( "This implies, hopefully you can see why, that 10 < w < 90.\r
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\n" ); document.write( "\n" ); document.write( "However, because w < l , we also have that w < 50,
\n" ); document.write( "from equation 2, or from l = 100-w.
\n" ); document.write( "Therefore, the answer is 10 < w < 50.\r
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