document.write( "Question 96922: I can not find the solutions to this problem please help with a way i can come to the answer 2x^2+11x-1=0 thank you \n" ); document.write( "
Algebra.Com's Answer #70548 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 \"2%2Ax%5E2%2B11%2Ax-1=0\" ( notice \"a=2\", \"b=11\", and \"c=-1\")\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-11+%2B-+sqrt%28+%2811%29%5E2-4%2A2%2A-1+%29%29%2F%282%2A2%29\" Plug in a=2, b=11, and c=-1\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-11+%2B-+sqrt%28+121-4%2A2%2A-1+%29%29%2F%282%2A2%29\" Square 11 to get 121 \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-11+%2B-+sqrt%28+121%2B8+%29%29%2F%282%2A2%29\" Multiply \"-4%2A-1%2A2\" to get \"8\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-11+%2B-+sqrt%28+129+%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( "\"x+=+%28-11+%2B-+sqrt%28129%29%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( "\"x+=+%28-11+%2B-+sqrt%28129%29%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( "\"x+=+%28-11+%2B+sqrt%28129%29%29%2F4\" or \"x+=+%28-11+-+sqrt%28129%29%29%2F4\"\r
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\n" ); document.write( "\n" ); document.write( "Now break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"x=-11%2F4%2Bsqrt%28129%29%2F4\" or \"x=-11%2F4-sqrt%28129%29%2F4\"\r
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\n" ); document.write( "\n" ); document.write( "Simplify\r
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\n" ); document.write( "\n" ); document.write( "\"x=-11+%2F+4%2Bsqrt%28129%29%2F4\" or \"x=-11+%2F+4-sqrt%28129%29%2F4\"\r
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\n" ); document.write( "\n" ); document.write( "So these expressions approximate to\r
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\n" ); document.write( "\n" ); document.write( "\"x=0.0894541729001368\" or \"x=-5.58945417290014\"\r
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\n" ); document.write( "\n" ); document.write( "So our solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"x=0.0894541729001368\" or \"x=-5.58945417290014\"\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph \"2%2Ax%5E2%2B11%2Ax-1\", 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=0.0894541729001368\" and \"x=-5.58945417290014\".So this verifies our answer
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