document.write( "Question 350956: write the equation of the best-fit line in slope intercept form using the two data points given (9,-3)(5,-5) \n" ); document.write( "
Algebra.Com's Answer #250843 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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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=9\" and \"y%5B1%5D=-3\".\r
\n" ); document.write( "\n" ); document.write( "Also, is the second point . So this means that \"x%5B2%5D=5\" and \"y%5B2%5D=-5\".\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=%28-5--3%29%2F%285-9%29\" Plug in \"y%5B2%5D=-5\", \"y%5B1%5D=-3\", \"x%5B2%5D=5\", and \"x%5B1%5D=9\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-2%29%2F%285-9%29\" Subtract \"-3\" from \"-5\" to get \"-2\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-2%29%2F%28-4%29\" Subtract \"9\" from \"5\" to get \"-4\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=1%2F2\" 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=1%2F2\"\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--3=%281%2F2%29%28x-9%29\" Plug in \"m=1%2F2\", \"x%5B1%5D=9\", and \"y%5B1%5D=-3\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B3=%281%2F2%29%28x-9%29\" Rewrite \"y--3\" as \"y%2B3\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B3=%281%2F2%29x%2B%281%2F2%29%28-9%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B3=%281%2F2%29x-9%2F2\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=%281%2F2%29x-9%2F2-3\" Subtract 3 from both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"y=%281%2F2%29x-15%2F2\" Combine like terms. note: If you need help with fractions, check out this solver.\r
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\n" ); document.write( "\n" ); document.write( "So the equation that goes through the points and is \"y=%281%2F2%29x-15%2F2\"\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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