document.write( "Question 350964: Write the equation of the best-fit line in slope intercept form using the two data point given (1,6)(-1,2) \n" ); document.write( "
Algebra.Com's Answer #250857 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "First let's find the slope of the line through the points and \r
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\n" ); document.write( "\n" ); document.write( "Note: is the first point . So this means that \"x%5B1%5D=1\" and \"y%5B1%5D=6\".\r
\n" ); document.write( "\n" ); document.write( "Also, is the second point . So this means that \"x%5B2%5D=-1\" and \"y%5B2%5D=2\".\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=%282-6%29%2F%28-1-1%29\" Plug in \"y%5B2%5D=2\", \"y%5B1%5D=6\", \"x%5B2%5D=-1\", and \"x%5B1%5D=1\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-4%29%2F%28-1-1%29\" Subtract \"6\" from \"2\" to get \"-4\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-4%29%2F%28-2%29\" Subtract \"1\" from \"-1\" to get \"-2\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=2\" 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=2\"\r
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\n" ); document.write( "\n" ); document.write( "Now let's use the point slope formula:\r
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\n" ); document.write( "\n" ); document.write( "\"y-y%5B1%5D=m%28x-x%5B1%5D%29\" Start with the point slope formula\r
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\n" ); document.write( "\n" ); document.write( "\"y-6=2%28x-1%29\" Plug in \"m=2\", \"x%5B1%5D=1\", and \"y%5B1%5D=6\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-6=2x%2B2%28-1%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y-6=2x-2\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=2x-2%2B6\" Add 6 to both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"y=2x%2B4\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "So the equation that goes through the points and is \"y=2x%2B4\"\r
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\n" ); document.write( "\n" ); document.write( " Notice how the graph of \"y=2x%2B4\" goes through the points and . So this visually verifies our answer.\r
\n" ); document.write( "\n" ); document.write( " Graph of \"y=2x%2B4\" through the points and \r
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\n" ); document.write( "\n" ); document.write( "If you need more help, email me at jim_thompson5910@hotmail.com\r
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\n" ); document.write( "\n" ); document.write( "Also, feel free to check out my tutoring website\r
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\n" ); document.write( "\n" ); document.write( "Jim
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