document.write( "Question 88959: Could you please help me with the following problem? I am supposed to solve this equation using the quadratic formula. (1/y)-(1/y+5)=(1/4)\r
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Algebra.Com's Answer #64659 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"1%2Fy-1%2F%28y%2B5%29=1%2F4\"\r
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\n" ); document.write( "\n" ); document.write( "\"4y%28y%2B5%29%281%2Fy-1%2F%28y%2B5%29%29=4y%28y%2B5%29%281%2F4%29\" Multiply both sides by the LCD 4y(y+5)\r
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\n" ); document.write( "\n" ); document.write( "\"4%28y%2B5%29-4y=y%28y%2B5%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"4y%2B20-4y=y%5E2%2B5y\" Distribute again\r
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\n" ); document.write( "\n" ); document.write( "\"20=y%5E2%2B5y\" Combine like terms\r
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\n" ); document.write( "\n" ); document.write( "\"0=y%5E2%2B5y-20\" Subtract 20 from both sides\r
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\n" ); document.write( "\n" ); document.write( "Now let's use the quadratic formula to solve for y:\r
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\n" ); document.write( "\n" ); document.write( "Starting with the general quadratic\r
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\n" ); document.write( "\n" ); document.write( "\"ay%5E2%2Bby%2Bc=0\"\r
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\n" ); document.write( "\n" ); document.write( "the general solution using the quadratic equation is:\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\"\r
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\n" ); document.write( "\n" ); document.write( "So lets solve \"y%5E2%2B5%2Ay-20=0\" ( notice \"a=1\", \"b=5\", and \"c=-20\")\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28-5+%2B-+sqrt%28+%285%29%5E2-4%2A1%2A-20+%29%29%2F%282%2A1%29\" Plug in a=1, b=5, and c=-20\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28-5+%2B-+sqrt%28+25-4%2A1%2A-20+%29%29%2F%282%2A1%29\" Square 5 to get 25\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28-5+%2B-+sqrt%28+25%2B80+%29%29%2F%282%2A1%29\" Multiply \"-4%2A-20%2A1\" to get \"80\"\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28-5+%2B-+sqrt%28+105+%29%29%2F%282%2A1%29\" Combine like terms in the radicand (everything under the square root)\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28-5+%2B-+sqrt%28105%29%29%2F%282%2A1%29\" Simplify the square root\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28-5+%2B-+sqrt%28105%29%29%2F2\" Multiply 2 and 1 to get 2\r
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\n" ); document.write( "\n" ); document.write( "So now the expression breaks down into two parts\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28-5+%2B+sqrt%28105%29%29%2F2\" or \"y+=+%28-5+-+sqrt%28105%29%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "which split up to\r
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\n" ); document.write( "\n" ); document.write( "\"y=-5%2F2%2Bsqrt%28105%29%2F2\" or \"y=-5%2F2-sqrt%28105%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "Which approximate to\r
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\n" ); document.write( "\n" ); document.write( "\"y=2.6234753829798\" or \"y=-7.6234753829798\"\r
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\n" ); document.write( "\n" ); document.write( "So our solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"y=2.6234753829798\" or \"y=-7.6234753829798\"\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph \"x%5E2%2B5%2Ax-20\" (just replace y with x), we get:\r
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\n" ); document.write( "\n" ); document.write( "when we use the root finder feature on a calculator, we find that \"x=2.6234753829798\" and \"x=-7.6234753829798\".So this verifies our answer
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