document.write( "Question 96893: x squared-x-6=0 \n" ); document.write( "
Algebra.Com's Answer #70523 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-x-6=0\" ( notice \"a=1\", \"b=-1\", and \"c=-6\")\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28--1+%2B-+sqrt%28+%28-1%29%5E2-4%2A1%2A-6+%29%29%2F%282%2A1%29\" Plug in a=1, b=-1, and c=-6\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%281+%2B-+sqrt%28+%28-1%29%5E2-4%2A1%2A-6+%29%29%2F%282%2A1%29\" Negate -1 to get 1\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%281+%2B-+sqrt%28+1-4%2A1%2A-6+%29%29%2F%282%2A1%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( "\"x+=+%281+%2B-+sqrt%28+1%2B24+%29%29%2F%282%2A1%29\" Multiply \"-4%2A-6%2A1\" to get \"24\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%281+%2B-+sqrt%28+25+%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+=+%281+%2B-+5%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+=+%281+%2B-+5%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+=+%281+%2B+5%29%2F2\" or \"x+=+%281+-+5%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=%281+%2B+5%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=6%2F2\" Add the terms in the numerator\r
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\n" ); document.write( "\n" ); document.write( "So one answer is\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+-+5%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=-4%2F2\" Subtract the terms in the numerator\r
\n" ); document.write( "\n" ); document.write( "\"x=-2\" Divide\r
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\n" ); document.write( "\n" ); document.write( "So another answer is\r
\n" ); document.write( "\n" ); document.write( "\"x=-2\"\r
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\n" ); document.write( "\n" ); document.write( "So our solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"x=3\" or \"x=-2\"\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph \"x%5E2-x-6\", we get:\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C+-12%2C+13%2C+-12%2C+13%2C1%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 \"x=3\" and \"x=-2\". This verifies our answer
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