document.write( "Question 550327: write the equation of the line though (5,-2) and (2,10) \n" ); document.write( "
Algebra.Com's Answer #358613 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=-2\".\r
\n" ); document.write( "\n" ); document.write( "Also, is the second point . So this means that \"x%5B2%5D=2\" and \"y%5B2%5D=10\".\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=%2810--2%29%2F%282-5%29\" Plug in \"y%5B2%5D=10\", \"y%5B1%5D=-2\", \"x%5B2%5D=2\", and \"x%5B1%5D=5\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%2812%29%2F%282-5%29\" Subtract \"-2\" from \"10\" to get \"12\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%2812%29%2F%28-3%29\" Subtract \"5\" from \"2\" to get \"-3\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=-4\" 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=-4\"\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=-4%28x-5%29\" Plug in \"m=-4\", \"x%5B1%5D=5\", and \"y%5B1%5D=-2\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B2=-4%28x-5%29\" Rewrite \"y--2\" as \"y%2B2\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B2=-4x%2B-4%28-5%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B2=-4x%2B20\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=-4x%2B20-2\" Subtract 2 from both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"y=-4x%2B18\" 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=-4x%2B18\"\r
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\n" ); document.write( "\n" ); document.write( " Notice how the graph of \"y=-4x%2B18\" goes through the points and . So this visually verifies our answer.\r
\n" ); document.write( "\n" ); document.write( " Graph of \"y=-4x%2B18\" through the points and \r
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