document.write( "Question 200467: How do i do this? Write the equation of the line perpendicular to - 3x - 4y = 10 with a y-intercept of -5. Thank you. \n" ); document.write( "
Algebra.Com's Answer #150720 by jim_thompson5910(35256)\"\" \"About 
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If a line has \"a y-intercept of -5\", then it goes through the point (0,-5) \r
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\n" ); document.write( "\n" ); document.write( "\"-3x-4y=10\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-4y=10%2B3x\" Add \"3x\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-4y=3x%2B10\" Rearrange the terms.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%283x%2B10%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%283%29%2F%28-4%29%29x%2B%2810%29%2F%28-4%29\" Break up the fraction.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-%283%2F4%29x-5%2F2\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "We can see that the equation \"y=-%283%2F4%29x-5%2F2\" has a slope \"m=-3%2F4\" and a y-intercept \"b=-5%2F2\".\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--5=%284%2F3%29%28x-0%29\" Plug in \"m=4%2F3\", \"x%5B1%5D=0\", and \"y%5B1%5D=-5\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B5=%284%2F3%29%28x-0%29\" Rewrite \"y--5\" as \"y%2B5\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B5=%284%2F3%29x-%284%2F3%29%280%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B5=%284%2F3%29x%2B0\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=%284%2F3%29x%2B0-5\" Subtract 5 from both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"y=%284%2F3%29x-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=10\" that goes through the point is \"y=%284%2F3%29x-5\".\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=-%283%2F4%29x-5%2F2\" (red) and the perpendicular line \"y=%284%2F3%29x-5\" (green) through the point .
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