document.write( "Question 193133: Solve z^2+z=5\r
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Algebra.Com's Answer #144975 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "\"z%5E2%2Bz=5\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"z%5E2%2Bz-5=0\" Subtract 5 from both sides.\r
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\n" ); document.write( "\n" ); document.write( "Notice we have a quadratic equation in the form of \"az%5E2%2Bbz%2Bc=0\" where \"a=1\", \"b=1\", and \"c=-5\"\r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for z\r
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\n" ); document.write( "\n" ); document.write( "\"z+=+%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( "\"z+=+%28-%281%29+%2B-+sqrt%28+%281%29%5E2-4%281%29%28-5%29+%29%29%2F%282%281%29%29\" Plug in \"a=1\", \"b=1\", and \"c=-5\"\r
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\n" ); document.write( "\n" ); document.write( "\"z+=+%28-1+%2B-+sqrt%28+1-4%281%29%28-5%29+%29%29%2F%282%281%29%29\" Square \"1\" to get \"1\". \r
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\n" ); document.write( "\n" ); document.write( "\"z+=+%28-1+%2B-+sqrt%28+1--20+%29%29%2F%282%281%29%29\" Multiply \"4%281%29%28-5%29\" to get \"-20\"\r
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\n" ); document.write( "\n" ); document.write( "\"z+=+%28-1+%2B-+sqrt%28+1%2B20+%29%29%2F%282%281%29%29\" Rewrite \"sqrt%281--20%29\" as \"sqrt%281%2B20%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"z+=+%28-1+%2B-+sqrt%28+21+%29%29%2F%282%281%29%29\" Add \"1\" to \"20\" to get \"21\"\r
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\n" ); document.write( "\n" ); document.write( "\"z+=+%28-1+%2B-+sqrt%28+21+%29%29%2F%282%29\" Multiply \"2\" and \"1\" to get \"2\". \r
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\n" ); document.write( "\n" ); document.write( "\"z+=+%28-1%2Bsqrt%2821%29%29%2F%282%29\" or \"z+=+%28-1-sqrt%2821%29%29%2F%282%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "So the answers are \"z+=+%28-1%2Bsqrt%2821%29%29%2F%282%29\" or \"z+=+%28-1-sqrt%2821%29%29%2F%282%29\" \r
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\n" ); document.write( "\n" ); document.write( "which approximate to \"z=1.791\" or \"z=-2.791\" (using a calculator)
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