document.write( "Question 321515: Find an equation for the line that passes through the points (5, -4) and (1, -2) \n" ); document.write( "
Algebra.Com's Answer #230257 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=5\" and \"y%5B1%5D=-4\".\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=%28-2--4%29%2F%281-5%29\" Plug in \"y%5B2%5D=-2\", \"y%5B1%5D=-4\", \"x%5B2%5D=1\", and \"x%5B1%5D=5\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%282%29%2F%281-5%29\" Subtract \"-4\" from \"-2\" to get \"2\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%282%29%2F%28-4%29\" Subtract \"5\" from \"1\" 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--4=%28-1%2F2%29%28x-5%29\" Plug in \"m=-1%2F2\", \"x%5B1%5D=5\", and \"y%5B1%5D=-4\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B4=%28-1%2F2%29%28x-5%29\" Rewrite \"y--4\" as \"y%2B4\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B4=%28-1%2F2%29x%2B%28-1%2F2%29%28-5%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B4=%28-1%2F2%29x%2B5%2F2\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1%2F2%29x%2B5%2F2-4\" Subtract 4 from both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1%2F2%29x-3%2F2\" 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=%28-1%2F2%29x-3%2F2\"
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