document.write( "Question 936310: The Houston Astrodome was the first baseball
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\n" ); document.write( "have increased by approximately 6% each year
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\n" ); document.write( "If this rate were to continue, how much
\n" ); document.write( "would it have cost to build the Astrodome in
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Algebra.Com's Answer #569740 by AnlytcPhil(1806)\"\" \"About 
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The Houston Astrodome was the first baseball
\n" ); document.write( "and football stadium to be completely
\n" ); document.write( "enclosed. It was completed in 1965 at a cost
\n" ); document.write( "of 45.35 million dollars. Construction costs
\n" ); document.write( "have increased by approximately 6% each year
\n" ); document.write( "since 1965.
\n" ); document.write( "If this rate were to continue, how much
\n" ); document.write( "would it have cost to build the Astrodome in
\n" ); document.write( "2012?
\n" ); document.write( "
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document.write( "Let x = the year\r\n" );
document.write( "Let y = the cost to build\r\n" );
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document.write( "When x = 1965, y = 45.35 (million dollars)\r\n" );
document.write( "When x = 1966, y = 45.35 + 0.06(45.35) = 48.071 (million dollars)\r\n" );
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document.write( "We find the equation of the line which passes through the\r\n" );
document.write( "points (1965,45.35) and (1966,48.071)\r\n" );
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document.write( "We use the 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" );
document.write( "where (x1,y1) = (1965,45.35)\r\n" );
document.write( "and where (x2,y2) = (1966,48.071)\r\n" );
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document.write( "m = \"%2848.071-45.35%29%2F%281966-1965%29=2.721\"\r\n" );
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document.write( "We use the point-slope formula:\r\n" );
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document.write( "y - y1 = m(x - x1)\r\n" );
document.write( "where (x1,y1) = (1965,45.35)\r\n" );
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document.write( "y - 45.35 = 2.721(x - 1965)\r\n" );
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document.write( "y - 45.35 = 2.721x - 5346.765\r\n" );
document.write( "       \r\n" );
document.write( "        y = 2.721x - 5301.415\r\n" );
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document.write( "Sobstitute x = 2012:\r\n" );
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document.write( "        y = 2.721(2012) - 5301.415\r\n" );
document.write( "          \r\n" );
document.write( "        y = 173.237 million dollars or $173,237,000\r\n" );
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document.write( "Edwin
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