document.write( "Question 154214: Given the function f(x) = x^2 - x find the AVERAGE RATE of CHANGE of f from 3 to 5 \n" ); document.write( "
Algebra.Com's Answer #113587 by jim_thompson5910(35256)\"\" \"About 
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\"f%28x%29+=+x%5E2+-+x\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"f%283%29+=+%283%29%5E2+-+3\" Plug in \"x=3\"\r
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\n" ); document.write( "\n" ); document.write( "\"f%283%29+=+9+-+3\" Square 3 to get 9\r
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\n" ); document.write( "\n" ); document.write( "\"f%283%29+=+6\" Subtract\r
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\n" ); document.write( "\n" ); document.write( "So the point (3,6) is on the graph\r
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\n" ); document.write( "\n" ); document.write( "\"f%28x%29+=+x%5E2+-+x\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"f%285%29+=+%285%29%5E2+-+5\" Plug in \"x=5\"\r
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\n" ); document.write( "\n" ); document.write( "\"f%285%29+=+25+-+5\" Square 5 to get 25\r
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\n" ); document.write( "\n" ); document.write( "\"f%285%29+=+20\" Subtract\r
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\n" ); document.write( "\n" ); document.write( "So the point (5,20) is on the graph\r
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\n" ); document.write( "\n" ); document.write( "So the average rate of change from x=3 to x=5 is simply the slope of the line that goes through the points (3,6) and (5,20)\r
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\n" ); document.write( "\n" ); document.write( "So let's find the slope of the line that goes through the points (3,6) and (5,20)\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29\" Start with the slope formula.\r
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\n" ); document.write( "\n" ); document.write( "\"m=%2820-6%29%2F%285-3%29\" Plug in \"y%5B2%5D=20\", \"y%5B1%5D=6\", \"x%5B2%5D=5\", and \"x%5B1%5D=3\" \r
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\n" ); document.write( "\n" ); document.write( "\"m=%2814%29%2F%285-3%29\" Subtract \"6\" from \"20\" to get \"14\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%2814%29%2F%282%29\" Subtract \"3\" from \"5\" to get \"2\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=7\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "So the slope of the line that goes through the points and is \"m=7\"\r
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\n" ); document.write( "\n" ); document.write( "Since the slope is 7, this means that the average rate of change from x=3 to x=5 is 7
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