document.write( "Question 567773: find an equation of the line that contains the following pair of points (4,1) (1,3) \n" ); document.write( "
Algebra.Com's Answer #366775 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=4\" and \"y%5B1%5D=1\".\r
\n" ); document.write( "\n" ); document.write( "Also, is the second point . So this means that \"x%5B2%5D=1\" and \"y%5B2%5D=3\".\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=%283-1%29%2F%281-4%29\" Plug in \"y%5B2%5D=3\", \"y%5B1%5D=1\", \"x%5B2%5D=1\", and \"x%5B1%5D=4\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%282%29%2F%281-4%29\" Subtract \"1\" from \"3\" to get \"2\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%282%29%2F%28-3%29\" Subtract \"4\" from \"1\" to get \"-3\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=-2%2F3\" 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%2F3\"\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-1=%28-2%2F3%29%28x-4%29\" Plug in \"m=-2%2F3\", \"x%5B1%5D=4\", and \"y%5B1%5D=1\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-1=%28-2%2F3%29x%2B%28-2%2F3%29%28-4%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y-1=%28-2%2F3%29x%2B8%2F3\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-2%2F3%29x%2B8%2F3%2B1\" Add 1 to both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-2%2F3%29x%2B11%2F3\" 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=%28-2%2F3%29x%2B11%2F3\"\r
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