document.write( "Question 959040: A college professor has purchased a new bicycle for commuting to class. This bicycle had a purchase price of $600 and depreciates at a constant rate of $55 a year. What is the bicycle’s value after 3.5 years? How long before the bicycle is worth zero?
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Algebra.Com's Answer #586140 by Edwin McCravy(20056)\"\" \"About 
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A college professor has purchased a new bicycle for commuting to class. This
\n" ); document.write( "bicycle had a purchase price of $600 and depreciates at a constant rate of $55 a
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document.write( "1. When 0 years have passed, the bicycle is worth $600\r\n" );
document.write( "2. When 1 year has passed, the bicycle is worth $600-$55 = $545\r\n" );
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document.write( "Let x = the number of years that have passed.\r\n" );
document.write( "Let y = the worth of the bicycle.\r\n" );
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document.write( "Then, the interpretation of the above two sentences are:\r\n" );
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document.write( "1. When x=0, y=600\r\n" );
document.write( "2. When x=1, y=545\r\n" );
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document.write( "The mathematical interpretation is:\r\n" );
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document.write( "Find the equation of the line that passes through the \r\n" );
document.write( "points (0,600) and (1,545)\r\n" );
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document.write( "Slope formula:\r\n" );
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document.write( "m = \"%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29\"\r\n" );
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document.write( "where (x1,y1) = (0,600)\r\n" );
document.write( "and where (x2,y2) = (1,545)\r\n" );
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document.write( "m = \"%28545-600%29%2F%281-0%29\"\r\n" );
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document.write( "m = \"-55%2F1\"\r\n" );
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document.write( "m = -55\r\n" );
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document.write( "Point-slope formula:\r\n" );
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document.write( "y - y1 = m(x - x1)\r\n" );
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document.write( "where (x1,y1) = (0,600) and m = -55\r\n" );
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document.write( "y - 600 = -55(x - 0)\r\n" );
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document.write( "y - 600 = -55x \r\n" );
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document.write( "y = -55x + 600\r\n" );
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\n" ); document.write( "What is the bicycle’s value after 3.5 years?
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document.write( "Plug in 3.5 years for x, solve for y dollars:\r\n" );
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document.write( "y = -55(3.5) + 600\r\n" );
document.write( "y = $407.50\r\n" );
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\n" ); document.write( "How long before the bicycle is worth zero?
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document.write( "Plug in 0 dollars for y, solve for x years.\r\n" );
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document.write( "0 = -55x + 600\r\n" );
document.write( "55x = 600\r\n" );
document.write( "  x = 600/55 = \"10%2610%2F11\" years.\r\n" );
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document.write( "Edwin
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