document.write( "Question 701788: What is the equation of the line that passes through the points (-1,5) and (2,-4) \n" ); document.write( "
Algebra.Com's Answer #432591 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=5\".\r
\n" ); document.write( "\n" ); document.write( "Also, is the second point . So this means that \"x%5B2%5D=2\" and \"y%5B2%5D=-4\".\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=%28-4-5%29%2F%282--1%29\" Plug in \"y%5B2%5D=-4\", \"y%5B1%5D=5\", \"x%5B2%5D=2\", and \"x%5B1%5D=-1\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-9%29%2F%282--1%29\" Subtract \"5\" from \"-4\" to get \"-9\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-9%29%2F%283%29\" Subtract \"-1\" from \"2\" to get \"3\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=-3\" 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=-3\"\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-5=-3%28x--1%29\" Plug in \"m=-3\", \"x%5B1%5D=-1\", and \"y%5B1%5D=5\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-5=-3%28x%2B1%29\" Rewrite \"x--1\" as \"x%2B1\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-5=-3x%2B-3%281%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y-5=-3x-3\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=-3x-3%2B5\" Add 5 to both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"y=-3x%2B2\" 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=-3x%2B2\"\r
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