document.write( "Question 170177: Find the equation of the line perpendicular to 3x-4y=9 and passing through (2,-1). Write the equation in standard form, with all integer coefficients. \n" ); document.write( "
Algebra.Com's Answer #125614 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "\"3x-4y=9\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-4y=9-3x\" Subtract \"3x\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-4y=-3x%2B9\" Rearrange the terms.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-3x%2B9%29%2F%28-4%29\" Divide both sides by \"-4\" to isolate y.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28%28-3%29%2F%28-4%29%29x%2B%289%29%2F%28-4%29\" Break up the fraction.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%283%2F4%29x-9%2F4\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "We can see that the equation \"y=%283%2F4%29x-9%2F4\" has a slope \"m=3%2F4\" and a y-intercept \"b=-9%2F4\".\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=3%2F4\" to get \"m=4%2F3\". Now change the sign to get \"m=-4%2F3\". So the perpendicular slope is \"m=-4%2F3\".\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=3%2F4\" 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=%28-4%2F3%29%28x-2%29\" Plug in \"m=-4%2F3\", \"x%5B1%5D=2\", and \"y%5B1%5D=-1\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B1=%28-4%2F3%29%28x-2%29\" Rewrite \"y--1\" as \"y%2B1\"\r
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\n" ); document.write( "\n" ); document.write( "\"3%28y%2B1%29=-4%28x-2%29\" Multiply both sides by 3 to clear the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"3y%2B3=-4x%2B8\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"4x%2B3y=8-3\" Subtract 3 from both sides. Add 4x to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"4x%2B3y=5\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So the equation of the line perpendicular to \"3x-4y=9\" that goes through the point in standard form is \"4x%2B3y=5\".\r
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