document.write( "Question 129645: The manager of an 80 unit apartment complex is trying to deceide what rent to charge. Experience has shown that at a rent of $200.00 all the units will be full but with one additional unit will remain vacant f0r each $20.00increase. Find the # of occupied unit if the total revenue is $20,020.
\n" ); document.write( "This is the problem I am trying to solve, however I am not clear on how or where to start it. If you could possibly show me the steps I would greatly appericate it. Thank you \r
\n" ); document.write( "\n" ); document.write( "1 solutions\r
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\n" ); document.write( "Answer 94355 by solver91311(860) on 2008-02-25 20:07:28: \r
\n" ); document.write( "\n" ); document.write( "You can put this solution on YOUR website!
\n" ); document.write( "Let x be the number of occupied units. Then 80 - x is the number of unoccupied units. \r
\n" ); document.write( "\n" ); document.write( "The rental fee is 200 plus 20 times the number of unoccupied units, so: \r
\n" ); document.write( "\n" ); document.write( ", which simplifies to: \r
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\n" ); document.write( "\n" ); document.write( "This is the amount charged per apartment, and there are x occupied apartments, so the total revenue is: \r
\n" ); document.write( "\n" ); document.write( " and that is equal to $20,020. \r
\n" ); document.write( "\n" ); document.write( "So: \r
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\n" ); document.write( "\n" ); document.write( "Divide by -20:
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\n" ); document.write( "\n" ); document.write( "You can factor this (the prime factors of 1001 are 7, 11, and 13), or use the quadratic formula, whichever you prefer, but the roots come out to be and , \r
\n" ); document.write( "\n" ); document.write( "So, if the rental fee is 200 + 20(3) = 260 (3 unoccupied units), then the total revenue is 77 * 260 = 20020. \r
\n" ); document.write( "\n" ); document.write( "But if the rental fee is 200 + 20(67) = 1540, then the total revenue is 13 * 1540, also = 20020. \r
\n" ); document.write( "\n" ); document.write( "The second root presumes that the relationship of rent to unoccupied units is linear across the entire range of possibilities, which I suspect is not the case in real life. \r
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\n" ); document.write( "\n" ); document.write( "***************This the help that I received and I understand it up to here,however how do you compute this into a quadratic equation? That is what I don't understand. Thank you for your time........................................
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Algebra.Com's Answer #94650 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
The manager of an 80 unit apartment complex is trying to deceide what rent to charge.
\n" ); document.write( "Experience has shown that at a rent of $200.00 all the units will be full but one additional unit will remain vacant f0r each $20.00 increase.
\n" ); document.write( "Find the # of occupied units if the total revenue is $20,020.
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\n" ); document.write( "Let \"x\" be the number of $20 increases.
\n" ); document.write( "Price per unit will be (200+20x)
\n" ); document.write( "# of units occupied will be (80-x)
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\n" ); document.write( "EQUATION:
\n" ); document.write( "Revenue = price per unit * # of units occupied:
\n" ); document.write( "20,020 = (200+20x)(80-x)
\n" ); document.write( "-20x^2 +1600x-200x + 16000 = 20,020
\n" ); document.write( "-20x^2+1400x -4020 = 0
\n" ); document.write( "Divide thru by -20 to get:
\n" ); document.write( "x^2-70s+201=0
\n" ); document.write( "Factor to get:
\n" ); document.write( "(x-67)(x+3)=0
\n" ); document.write( "Positive answer:
\n" ); document.write( "x = 67 (The number of $20 raises)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.\r
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