document.write( "Question 174200: What is the equation of the line that passes through the given point and is perpendicular to the given line?\r
\n" ); document.write( "\n" ); document.write( "(8,-1), 4y + 2x = 12
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\n" ); document.write( "i got y= -2x-3.\r
\n" ); document.write( "\n" ); document.write( "I tried my best, but didn't quite understand the problem, so it would be great if you could check my answer. Thankyou so much!
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Algebra.Com's Answer #129136 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "\"4y+%2B+2x+=+12\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"4y=12-2x\" Subtract \"2x\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"4y=-2x%2B12\" Rearrange the terms.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-2x%2B12%29%2F%284%29\" Divide both sides by \"4\" to isolate y.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28%28-2%29%2F%284%29%29x%2B%2812%29%2F%284%29\" Break up the fraction.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-%281%2F2%29x%2B3\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "We can see that the equation \"y=-%281%2F2%29x%2B3\" has a slope \"m=-1%2F2\" and a y-intercept \"b=3\".\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%2F2\" to get \"m=-2%2F1\". Now change the sign to get \"m=2\". So the perpendicular slope is \"m=2\".\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%2F2\" 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--1=2%28x-8%29\" Plug in \"m=2\", \"x%5B1%5D=8\", and \"y%5B1%5D=-1\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B1=2%28x-8%29\" Rewrite \"y--1\" as \"y%2B1\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B1=2x%2B2%28-8%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B1=2x-16\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=2x-16-1\" Subtract 1 from both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"y=2x-17\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "So the equation of the line perpendicular to \"2x%2B4y=+12\" that goes through the point is \"y=2x-17\".\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%2F2%29x%2B3\" (red) and the perpendicular line \"y=2x-17\" (green) through the point .
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