document.write( "Question 451297: Write an equation of the line the passes through (-5,8) and (-3,-8) \n" ); document.write( "
Algebra.Com's Answer #310349 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=8\".\r
\n" ); document.write( "\n" ); document.write( "Also, is the second point . So this means that \"x%5B2%5D=-3\" 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=%28-8-8%29%2F%28-3--5%29\" Plug in \"y%5B2%5D=-8\", \"y%5B1%5D=8\", \"x%5B2%5D=-3\", and \"x%5B1%5D=-5\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-16%29%2F%28-3--5%29\" Subtract \"8\" from \"-8\" to get \"-16\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=%28-16%29%2F%282%29\" Subtract \"-5\" from \"-3\" to get \"2\"\r
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\n" ); document.write( "\n" ); document.write( "\"m=-8\" 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=-8\"\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-8=-8%28x--5%29\" Plug in \"m=-8\", \"x%5B1%5D=-5\", and \"y%5B1%5D=8\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-8=-8%28x%2B5%29\" Rewrite \"x--5\" as \"x%2B5\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-8=-8x%2B-8%285%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y-8=-8x-40\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=-8x-40%2B8\" Add 8 to both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"y=-8x-32\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"y=-8x-32\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "So the equation that goes through the points and is \"y=-8x-32\"\r
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\n" ); document.write( "\n" ); document.write( " Notice how the graph of \"y=-8x-32\" goes through the points and . So this visually verifies our answer.\r
\n" ); document.write( "\n" ); document.write( " Graph of \"y=-8x-32\" through the points and \r
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