document.write( "Question 157496: I trying to find the inverse of a function. I have to solve for y but I don't know how to do this when there is a variable on the top and bottom.\r
\n" ); document.write( "\n" ); document.write( "x(x-5)= y ----------> y(y-5)=x ???
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Algebra.Com's Answer #116059 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
I'll start where you left off\r
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\n" ); document.write( "\n" ); document.write( "\"y%28y-5%29=x\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"y%5E2-5y=x\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y%5E2-5y-x=0\" Subtract \"x\" from both sides\r
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\n" ); document.write( "\n" ); document.write( "Notice how we have a quadratic equation in the form of \"ay%5E2%2Bby%2Bc\" where \"a=1\", \"b=-5\", and \"c=-x\". So to solve for y, we must use the quadratic formula \"y+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\" Start with the quadratic formula\r
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\n" ); document.write( "\n" ); document.write( " Plug in \"a=1\", \"b=-5\", and \"c=-x\"\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%285+%2B-+sqrt%28+25%2B4x+%29%29%2F%282%29+\" Multiply and simplify\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%285+%2B+sqrt%28+25%2B4x+%29%29%2F%282%29+\" or \"y+=+%285+-+sqrt%28+25%2B4x+%29%29%2F%282%29+\" Break up the \"plus/minus\"\r
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\n" ); document.write( "\n" ); document.write( "So the inverse of \"x%28x-5%29=+y\" is \"y+=+%285+%2B+sqrt%28+25%2B4x+%29%29%2F%282%29+\" or \"y+=+%285+-+sqrt%28+25%2B4x+%29%29%2F%282%29+\" \r
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\n" ); document.write( "\n" ); document.write( "Note: the inverse of \"x%28x-5%29=+y\" is NOT a function.
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