document.write( "Question 425275: Hello, I need help with an exponential growth model word problem :
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document.write( "The population of Houston Texas was 2.30 million in 1990, and 2.65 million in 2000. Using an exponential growth model, , sketch a graph of the population beginning in 1990 and find the predicted population in 2010\r
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document.write( "I checked my exponential growth notes but the formula was not the same it is: and we found the vertex from that (which is the \"h\" and \"k\"), then made our graphs. I checked online and there was a calculater for it and that gave me an answer of 76.16554 which I do not think has anything to do with this question. Thank you so much for your time. \n" );
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Algebra.Com's Answer #296169 by stanbon(75887) ![]() You can put this solution on YOUR website! The population of Houston Texas was 2.30 million in 1990, \n" ); document.write( "and 2.65 million in 2000. Using an exponential growth model, y = ne^kt , sketch a graph of the population beginning in 1990 and find the predicted population in 2010 \n" ); document.write( "---- \n" ); document.write( "In 2000 t is 10 \n" ); document.write( "2.65 = n*e^10k \n" ); document.write( "In 1990 t is zero. \n" ); document.write( "2.30 = n*e^0 \n" ); document.write( "--- \n" ); document.write( "So n = 2.30 \n" ); document.write( "--- \n" ); document.write( "So 2.65 = 2.30*e^10k \n" ); document.write( "--- \n" ); document.write( "So e^10k = 1.152174 \n" ); document.write( "Take the natural log of both sides to get: \n" ); document.write( "10k = 0.141651 \n" ); document.write( "k = 0.014165 \n" ); document.write( "--- \n" ); document.write( "Equation: \n" ); document.write( "y = 2.30*e^(0.014165t) \n" ); document.write( "find the predicted population in 2010 \n" ); document.write( "In 2010 t = 20 \n" ); document.write( "y = 2.30*e^(0.014165*20) \n" ); document.write( "y = 3.053258 million \n" ); document.write( "========================= \n" ); document.write( "Graph: \n" ); document.write( " \n" ); document.write( "========================= \n" ); document.write( "Cheers, \n" ); document.write( "Stan H. \n" ); document.write( "============= \n" ); document.write( " |