document.write( "Question 238656: I need help to figure out the x. the problem is \"4x%5E2%2B3x-8=0\"
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Algebra.Com's Answer #175342 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%2B3x-8=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "Notice that the quadratic \"4x%5E2%2B3x-8\" is in the form of \"Ax%5E2%2BBx%2BC\" where \"A=4\", \"B=3\", and \"C=-8\"\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-%283%29+%2B-+sqrt%28+%283%29%5E2-4%284%29%28-8%29+%29%29%2F%282%284%29%29\" Plug in \"A=4\", \"B=3\", and \"C=-8\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-3+%2B-+sqrt%28+9-4%284%29%28-8%29+%29%29%2F%282%284%29%29\" Square \"3\" to get \"9\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-3+%2B-+sqrt%28+9--128+%29%29%2F%282%284%29%29\" Multiply \"4%284%29%28-8%29\" to get \"-128\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-3+%2B-+sqrt%28+9%2B128+%29%29%2F%282%284%29%29\" Rewrite \"sqrt%289--128%29\" as \"sqrt%289%2B128%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-3+%2B-+sqrt%28+137+%29%29%2F%282%284%29%29\" Add \"9\" to \"128\" to get \"137\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-3+%2B-+sqrt%28+137+%29%29%2F%288%29\" Multiply \"2\" and \"4\" to get \"8\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-3%2Bsqrt%28137%29%29%2F%288%29\" or \"x+=+%28-3-sqrt%28137%29%29%2F%288%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x+=+%28-3%2Bsqrt%28137%29%29%2F%288%29\" or \"x+=+%28-3-sqrt%28137%29%29%2F%288%29\" \r
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\n" ); document.write( "\n" ); document.write( "which approximate to \"x=1.088\" or \"x=-1.838\"
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