document.write( "Question 383185: What is the equation of a line containing points (-1,2) and (5,-1) \n" ); document.write( "
Algebra.Com's Answer #271387 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( "\"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=%28-1-2%29%2F%285--1%29\" Plug in \"y%5B2%5D=-1\", \"y%5B1%5D=2\", \"x%5B2%5D=5\", and \"x%5B1%5D=-1\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-3%29%2F%285--1%29\" Subtract \"2\" from \"-1\" to get \"-3\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-3%29%2F%286%29\" Subtract \"-1\" from \"5\" to get \"6\"\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-2=%28-1%2F2%29%28x--1%29\" Plug in \"m=-1%2F2\", \"x%5B1%5D=-1\", and \"y%5B1%5D=2\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-2=%28-1%2F2%29%28x%2B1%29\" Rewrite \"x--1\" as \"x%2B1\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-2=%28-1%2F2%29x%2B%28-1%2F2%29%281%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y-2=%28-1%2F2%29x-1%2F2\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1%2F2%29x-1%2F2%2B2\" Add 2 to both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1%2F2%29x%2B3%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=%28-1%2F2%29x%2B3%2F2\"\r
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