document.write( "Question 113992: Solve the quadratic equation using the Quadratic Formula:
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Algebra.Com's Answer #82950 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"2y%5E2-y=6\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"2y%5E2-y-6=0\" Subtract 6 from both sides\r
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\n" ); document.write( "\n" ); document.write( "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 \"2%2Ay%5E2-y-6=0\" ( notice \"a=2\", \"b=-1\", and \"c=-6\")\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28--1+%2B-+sqrt%28+%28-1%29%5E2-4%2A2%2A-6+%29%29%2F%282%2A2%29\" Plug in a=2, b=-1, and c=-6\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%281+%2B-+sqrt%28+%28-1%29%5E2-4%2A2%2A-6+%29%29%2F%282%2A2%29\" Negate -1 to get 1\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%281+%2B-+sqrt%28+1-4%2A2%2A-6+%29%29%2F%282%2A2%29\" Square -1 to get 1 (note: remember when you square -1, you must square the negative as well. This is because \"%28-1%29%5E2=-1%2A-1=1\".)\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%281+%2B-+sqrt%28+1%2B48+%29%29%2F%282%2A2%29\" Multiply \"-4%2A-6%2A2\" to get \"48\"\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%281+%2B-+sqrt%28+49+%29%29%2F%282%2A2%29\" Combine like terms in the radicand (everything under the square root)\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%281+%2B-+7%29%2F%282%2A2%29\" Simplify the square root (note: If you need help with simplifying the square root, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%281+%2B-+7%29%2F4\" Multiply 2 and 2 to get 4\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+=+%281+%2B+7%29%2F4\" or \"y+=+%281+-+7%29%2F4\"\r
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\n" ); document.write( "\n" ); document.write( "Lets look at the first part:\r
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\n" ); document.write( "\n" ); document.write( "\"x=%281+%2B+7%29%2F4\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=8%2F4\" Add the terms in the numerator\r
\n" ); document.write( "\n" ); document.write( "\"y=2\" Divide\r
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\n" ); document.write( "\n" ); document.write( "So one answer is\r
\n" ); document.write( "\n" ); document.write( "\"y=2\"\r
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\n" ); document.write( "\n" ); document.write( "Now lets look at the second part:\r
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\n" ); document.write( "\n" ); document.write( "\"x=%281+-+7%29%2F4\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-6%2F4\" Subtract the terms in the numerator\r
\n" ); document.write( "\n" ); document.write( "\"y=-3%2F2\" Divide\r
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\n" ); document.write( "\n" ); document.write( "So another answer is\r
\n" ); document.write( "\n" ); document.write( "\"y=-3%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "So our solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"y=2\" or \"y=-3%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph \"2%2Ax%5E2-x-6\" (just replace y with x), we get:\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C+-13%2C+12%2C+-13%2C+12%2C2%2Ax%5E2%2B-1%2Ax%2B-6%29+\"\r
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\n" ); document.write( "\n" ); document.write( "and we can see that the roots are \"y=2\" and \"y=-3%2F2\". This verifies our answer
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