document.write( "Question 499813: (-1,4)and (5,-8) \n" ); document.write( "
Algebra.Com's Answer #337865 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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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=4\".\r
\n" ); document.write( "\n" ); document.write( "Also, is the second point . So this means that \"x%5B2%5D=5\" and \"y%5B2%5D=-8\".\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=%28-8-4%29%2F%285--1%29\" Plug in \"y%5B2%5D=-8\", \"y%5B1%5D=4\", \"x%5B2%5D=5\", and \"x%5B1%5D=-1\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-12%29%2F%285--1%29\" Subtract \"4\" from \"-8\" to get \"-12\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-12%29%2F%286%29\" Subtract \"-1\" from \"5\" to get \"6\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=-2\" 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=-2\"\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=-2%28x--1%29\" Plug in \"m=-2\", \"x%5B1%5D=-1\", and \"y%5B1%5D=4\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-4=-2%28x%2B1%29\" Rewrite \"x--1\" as \"x%2B1\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-4=-2x%2B-2%281%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y-4=-2x-2\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=-2x-2%2B4\" Add 4 to both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"y=-2x%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=-2x%2B2\"\r
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\n" ); document.write( "\n" ); document.write( " Notice how the graph of \"y=-2x%2B2\" goes through the points and . So this visually verifies our answer.\r
\n" ); document.write( "\n" ); document.write( " Graph of \"y=-2x%2B2\" through the points and \r
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\n" ); document.write( "\n" ); document.write( "If you need more help, feel free to email me at jim_thompson5910@hotmail.com\r
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\n" ); document.write( "\n" ); document.write( "Thanks,\r
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\n" ); document.write( "\n" ); document.write( "Jim
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