document.write( "Question 548465: Solve the equation: -x^2+4=2x^2-5 \n" ); document.write( "
Algebra.Com's Answer #358310 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "\"-x%5E2%2B4=2x%5E2-5\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-x%5E2%2B4-2x%5E2%2B5=0\" Get every term to the left side.\r
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\n" ); document.write( "\n" ); document.write( "\"-3x%5E2%2B9=0\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "Notice that the quadratic \"-3x%5E2%2B9\" is in the form of \"Ax%5E2%2BBx%2BC\" where \"A=-3\", \"B=0\", and \"C=9\"\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-%280%29+%2B-+sqrt%28+%280%29%5E2-4%28-3%29%289%29+%29%29%2F%282%28-3%29%29\" Plug in \"A=-3\", \"B=0\", and \"C=9\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-0+%2B-+sqrt%28+0-4%28-3%29%289%29+%29%29%2F%282%28-3%29%29\" Square \"0\" to get \"0\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-0+%2B-+sqrt%28+0--108+%29%29%2F%282%28-3%29%29\" Multiply \"4%28-3%29%289%29\" to get \"-108\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-0+%2B-+sqrt%28+0%2B108+%29%29%2F%282%28-3%29%29\" Rewrite \"sqrt%280--108%29\" as \"sqrt%280%2B108%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-0+%2B-+sqrt%28+108+%29%29%2F%282%28-3%29%29\" Add \"0\" to \"108\" to get \"108\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-0+%2B-+sqrt%28+108+%29%29%2F%28-6%29\" Multiply \"2\" and \"-3\" to get \"-6\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-0+%2B-+6%2Asqrt%283%29%29%2F%28-6%29\" Simplify the square root (note: If you need help with simplifying square roots, check out this solver) \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-0%29%2F%28-6%29+%2B-+%286%2Asqrt%283%29%29%2F%28-6%29\" Break up the fraction. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+0+%2B-+-1%2Asqrt%283%29\" Reduce. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+0-1%2Asqrt%283%29\" or \"x+=+0%2B1%2Asqrt%283%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x+=+-sqrt%283%29\" or \"x+=+sqrt%283%29\"
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