document.write( "Question 102533: I am having problems with this one.\r
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Algebra.Com's Answer #74568 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Let's use the quadratic formula to solve for x:\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( "\"ax%5E2%2Bbx%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( "\"x+=+%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 \"x%5E2%2B2%2Ax-8=0\" ( notice \"a=1\", \"b=2\", and \"c=-8\")\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-2+%2B-+sqrt%28+%282%29%5E2-4%2A1%2A-8+%29%29%2F%282%2A1%29\" Plug in a=1, b=2, and c=-8\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-2+%2B-+sqrt%28+4-4%2A1%2A-8+%29%29%2F%282%2A1%29\" Square 2 to get 4 \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-2+%2B-+sqrt%28+4%2B32+%29%29%2F%282%2A1%29\" Multiply \"-4%2A-8%2A1\" to get \"32\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-2+%2B-+sqrt%28+36+%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( "\"x+=+%28-2+%2B-+6%29%2F%282%2A1%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( "\"x+=+%28-2+%2B-+6%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( "\"x+=+%28-2+%2B+6%29%2F2\" or \"x+=+%28-2+-+6%29%2F2\"\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=%28-2+%2B+6%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=4%2F2\" Add the terms in the numerator\r
\n" ); document.write( "\n" ); document.write( "\"x=2\" Divide.....4,2....2 / 1\r
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\n" ); document.write( "\n" ); document.write( "So one answer is\r
\n" ); document.write( "\n" ); document.write( "\"x=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=%28-2+-+6%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=-8%2F2\" Subtract the terms in the numerator\r
\n" ); document.write( "\n" ); document.write( "\"x=-4\" Divide\r
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\n" ); document.write( "\n" ); document.write( "So another answer is\r
\n" ); document.write( "\n" ); document.write( "\"x=-4\"\r
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\n" ); document.write( "\n" ); document.write( "So our solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"x=2\" or \"x=-4\"\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph \"x%5E2%2B2%2Ax-8\", we get:\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C+-14%2C+12%2C+-14%2C+12%2C1%2Ax%5E2%2B2%2Ax%2B-8%29+\"\r
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\n" ); document.write( "\n" ); document.write( "and we can see that the roots are \"x=2\" and \"x=-4\". This verifies our answer
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