document.write( "Question 145656: Write an equation of the line that passes through the point at (4,4) and is perpendicular to the line whose equation is 2x+y=7??? \n" ); document.write( "
Algebra.Com's Answer #106295 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "\"2x%2By=7\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-2%2Ax%2B7\" Solve for y.\r
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\n" ); document.write( "\n" ); document.write( "We can see that the equation \"y=-2%2Ax%2B7\" has a slope \"m=-2\" and a y-intercept \"b=7\".\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=-2\" to get \"m=-1%2F2\". Now change the sign to get \"m=1%2F2\". So the perpendicular slope is \"m=1%2F2\".\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=-2\" 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-4=%281%2F2%29%28x-4%29\" Plug in \"m=1%2F2\", \"x%5B1%5D=4\", and \"y%5B1%5D=4\"\r
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\n" ); document.write( "\n" ); document.write( "\"y-4=%281%2F2%29x%2B%281%2F2%29%28-4%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y-4=%281%2F2%29x-2\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=%281%2F2%29x-2%2B4\" Add 4 to both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"y=%281%2F2%29x%2B2\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "So the equation of the line perpendicular to \"2x%2By=7\" that goes through the point is \"y=%281%2F2%29x%2B2\".\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=-2%2Ax%2B7\" (red) and the perpendicular line \"y=%281%2F2%29x%2B2\" (green) through the point .
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