document.write( "Question 200448: What is the equation of the line that contains the points with (x,y)coordinates (-3,7)and(5,-1)? \n" ); document.write( "
Algebra.Com's Answer #150712 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 and is the second point .\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=%28-1-7%29%2F%285--3%29\" Plug in \"y%5B2%5D=-1\", \"y%5B1%5D=7\", \"x%5B2%5D=5\", and \"x%5B1%5D=-3\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-8%29%2F%285--3%29\" Subtract \"7\" from \"-1\" to get \"-8\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-8%29%2F%288%29\" Subtract \"-3\" from \"5\" to get \"8\"\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-7=-1%28x--3%29\" Plug in \"m=-1\", \"x%5B1%5D=-3\", and \"y%5B1%5D=7\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-7=-1%28x%2B3%29\" Rewrite \"x--3\" as \"x%2B3\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-7=-1x%2B-1%283%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y-7=-1x-3\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=-1x-3%2B7\" Add 7 to both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"y=-1x%2B4\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"y=-x%2B4\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "So the equation that goes through the points and is \"y=-x%2B4\"\r
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\n" ); document.write( "\n" ); document.write( " Notice how the graph of \"y=-x%2B4\" goes through the points and . So this visually verifies our answer.\r
\n" ); document.write( "\n" ); document.write( " Graph of \"y=-x%2B4\" through the points and \r
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