document.write( "Question 623252: What is the equation of the line passing through the two points (-20,9) and (-15,4)? \n" ); document.write( "
Algebra.Com's Answer #391995 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=-20\" and \"y%5B1%5D=9\".\r
\n" ); document.write( "\n" ); document.write( "Also, is the second point . So this means that \"x%5B2%5D=-15\" 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=%284-9%29%2F%28-15--20%29\" Plug in \"y%5B2%5D=4\", \"y%5B1%5D=9\", \"x%5B2%5D=-15\", and \"x%5B1%5D=-20\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-5%29%2F%28-15--20%29\" Subtract \"9\" from \"4\" to get \"-5\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-5%29%2F%285%29\" Subtract \"-20\" from \"-15\" to get \"5\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=-1\" 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\"\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-9=-1%28x--20%29\" Plug in \"m=-1\", \"x%5B1%5D=-20\", and \"y%5B1%5D=9\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-9=-1%28x%2B20%29\" Rewrite \"x--20\" as \"x%2B20\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-9=-1x%2B-1%2820%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y-9=-1x-20\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=-1x-20%2B9\" Add 9 to both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"y=-1x-11\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"y=-x-11\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "So the equation that goes through the points and is \"y=-x-11\"
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