document.write( "Question 7792: What is the equation for a line that passes through (6,8) and is perpendicular to 9x+5y=94? \n" ); document.write( "
Algebra.Com's Answer #4294 by prince_abubu(198)\"\" \"About 
You can put this solution on YOUR website!
They give you the line 9x + 5y = 94, right? If you want to find the slope of the line perpendicular to the line given to you, you must first find the slope of the line given to you.\r
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\n" ); document.write( "\n" ); document.write( "9x + 5y = 94 needs some work. We need to change that around until we get it to say \"y = \".\r
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\n" ); document.write( "\n" ); document.write( "\"+9x+%2B+5y+=+94+\" <--- start here\r
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\n" ); document.write( "\n" ); document.write( "\"+5y+=+94+-+9x+\" <--- subtracted 9x from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"+y+=+94%2F5+-+%289%2F5%29x+\" <---- divide both sides by 5 so that the y can be alone finally. The -9/5 would be the slope of the line given to you.\r
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\n" ); document.write( "\n" ); document.write( "Now, the slope of the perpendicular is ALWAYS the negative (or opposite) reciprocal. If your slope is -9/5, then the opposite reciprocal will be 5/9. What you do is to flip the fraction and change the sign.\r
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\n" ); document.write( "\n" ); document.write( "Now, we know that the slope of the perpendicular line will be 5/9. They're given us some additional information. The perpendicular line passes through the point (6,8). There is a formula that exists that we can plug in the slope and a point. That would be \"+%28y+-+y%5B0%5D%29+=+m%28x+-+x%5B0%5D%29+\" where m is your slope, and (\"x%5B0%5D\",\"y%5B0%5D\") is a given point that the line goes through. Let's plug the values in:\r
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\n" ); document.write( "\n" ); document.write( "\"+%28y+-+8%29+=+%285%2F9%29%28x+-+6%29+\" <--- now this needs some work so that we can put it in standard form\r
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\n" ); document.write( "\n" ); document.write( "\"+9%28y+-+8%29+=+5%28x+-+6%29+\" <---- multiply the whole equation by 9 to get rid of the fraction.\r
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\n" ); document.write( "\n" ); document.write( "\"+9y+-+72+=+5x+-+30+\" <---- used distributive property.\r
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\n" ); document.write( "\n" ); document.write( "\"+-5x+%2B+9y+=+42+\" <---- moved the 5x to the left (as it became -5x) and added 72 to both sides. This is now our equation in standard form. This is the equation of the line perpendicular to 9x+5y=94.
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