document.write( "Question 425275: Hello, I need help with an exponential growth model word problem :
\n" ); document.write( "The population of Houston Texas was 2.30 million in 1990, and 2.65 million in 2000. Using an exponential growth model, \"+y+=+ne%5Ekt+\", sketch a graph of the population beginning in 1990 and find the predicted population in 2010\r
\n" ); document.write( "\n" ); document.write( "I checked my exponential growth notes but the formula was not the same it is: \"+y+=+a+sqrt%28+x-h+%29+%2B+k+\" 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.
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Algebra.Com's Answer #296169 by stanbon(75887)\"\" \"About 
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
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\n" ); document.write( "Graph:
\n" ); document.write( "\"graph%28400%2C300%2C-5%2C25%2C-5%2C5%2C2.30%2A%282.718281828%29%5E%280.014165x%29%29\"
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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