document.write( "Question 149331: Solve the following:\r
\n" ); document.write( "\n" ); document.write( "Passing through (5,-9) and perpendicular to x + 7y = 12
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Algebra.Com's Answer #109553 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "\"x+%2B+7y+=+12\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"7y+=+12-x\" Subtract x from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%2812-x%29%2F7\" Divide both sides by 7.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-%281%2F7%29x%2B12%2F7\" Break up the fraction and simplify.\r
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\n" ); document.write( "\n" ); document.write( "We can see that the equation \"y=-%281%2F7%29x%2B12%2F7\" has a slope \"m=-1%2F7\" and a y-intercept \"b=12%2F7\".\r
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\n" ); document.write( "\n" ); document.write( "Now to find the slope of the perpendicular line, simply flip the slope \"m=-1%2F7\" to get \"m=-7%2F1\". Now change the sign to get \"m=7\". So the perpendicular slope is \"m=7\".\r
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\n" ); document.write( "\n" ); document.write( "Now let's use the point slope formula to find the equation of the perpendicular line by plugging in the slope \"m=-1%2F7\" and the coordinates of the given point .\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=7%28x-5%29\" Plug in \"m=7\", \"x%5B1%5D=5\", and \"y%5B1%5D=-9\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B9=7%28x-5%29\" Rewrite \"y--9\" as \"y%2B9\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B9=7x%2B7%28-5%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B9=7x-35\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=7x-35-9\" Subtract 9 from both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"y=7x-44\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "So the equation of the line perpendicular to \"x+%2B+7y+=+12\" that goes through the point is \"y=7x-44\".\r
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\n" ); document.write( "\n" ); document.write( "Here's a graph to visually verify our answer:\r
\n" ); document.write( "\n" ); document.write( "Graph of the original equation \"y=-%281%2F7%29x%2B12%2F7\" (red) and the perpendicular line \"y=7x-44\" (green) through the point .
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