document.write( "Question 926130: 4x^2+x-20=0 \n" ); document.write( "

Algebra.Com's Answer #562037 by jim_thompson5910(35256) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( " $\"4x%5E2%2Bx-20=0\"$ Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "Notice that the quadratic $\"4x%5E2%2Bx-20\"$ is in the form of $\"Ax%5E2%2BBx%2BC\"$ where $\"A=4\"$ , $\"B=1\"$ , and $\"C=-20\"$ \r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for \"x\":\r
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\n" ); document.write( "\n" ); document.write( " $\"x+=+%28-B+%2B-+sqrt%28+B%5E2-4AC+%29%29%2F%282A%29\"$ Start with the quadratic formula\r
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\n" ); document.write( "\n" ); document.write( " $\"x+=+%28-%281%29+%2B-+sqrt%28+%281%29%5E2-4%284%29%28-20%29+%29%29%2F%282%284%29%29\"$ Plug in $\"A=4\"$ , $\"B=1\"$ , and $\"C=-20\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"x+=+%28-1+%2B-+sqrt%28+1-4%284%29%28-20%29+%29%29%2F%282%284%29%29\"$ Square $\"1\"$ to get $\"1\"$ . \r
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\n" ); document.write( "\n" ); document.write( " $\"x+=+%28-1+%2B-+sqrt%28+1--320+%29%29%2F%282%284%29%29\"$ Multiply $\"4%284%29%28-20%29\"$ to get $\"-320\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"x+=+%28-1+%2B-+sqrt%28+1%2B320+%29%29%2F%282%284%29%29\"$ Rewrite $\"sqrt%281--320%29\"$ as $\"sqrt%281%2B320%29\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"x+=+%28-1+%2B-+sqrt%28+321+%29%29%2F%282%284%29%29\"$ Add $\"1\"$ to $\"320\"$ to get $\"321\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"x+=+%28-1+%2B-+sqrt%28+321+%29%29%2F%288%29\"$ Multiply $\"2\"$ and $\"4\"$ to get $\"8\"$ . \r
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\n" ); document.write( "\n" ); document.write( " $\"x+=+%28-1%2Bsqrt%28321%29%29%2F%288%29\"$ or $\"x+=+%28-1-sqrt%28321%29%29%2F%288%29\"$ Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "So the exact solutions are $\"x+=+%28-1%2Bsqrt%28321%29%29%2F%288%29\"$ or $\"x+=+%28-1-sqrt%28321%29%29%2F%288%29\"$ \r
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\n" ); document.write( "\n" ); document.write( "If you need more one-on-one help, email me at jim_thompson5910@hotmail.com. You can ask me a few more questions for free, but afterwards, I would charge you ($2 a problem to have steps shown or $1 a problem for answer only).\r
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\n" ); document.write( "\n" ); document.write( "Jim\r
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